International VT 275 Engine Program II: Hard Start/No Start & Performance Diagnostics

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A NAVI STAR C O M PANY International VT 275 Engine Program II: Hard Start/No Start & Performance Diagnostics Study Guide TMT-120615 2006 International Truck and Engine Corporation, 4201 Winfield Road, Warrenville, IL 60555. All rights reserved. No part of this publication may be duplicated or stored in an information retrieval system without the express written permission of International Truck and Engine Corporation. Study Guide International VT 275 Engine Program II: Hard Start/No Start & Performance Diagnostics TMT-120615

Table of Contents Module I: Introduction... 2 Module II: Hard Start/No Start Diagnostics... 8 Initial Ignition Key-On... 8 Engine Cranking...10 Diagnostic Trouble Codes...11 Key-On Engine-Off Standard Test...13 Key-On Engine-Off Injector Test...14 EST Data List...15 Engine Systems...17 Engine Oil...20 Intake and Exhaust Restriction...21 Fuel Supply System...24 Main Power Relay Voltage to ECM...29 Main Power Relay Voltage to IDM...30 Low ICP System Pressure...31 Glow Plug System...40 Inlet Air Heater...41

Module III: Performance Diagnostics...46 Diagnostic Trouble Codes...46 Key-On Engine-Off Standard Test...46 Key-On Engine-Off Injector Test... 47 Engine Oil...47 Fuel...47 Intake and Exhaust Restriction... 47 Key-On Engine-Running Standard Test...48 Injection Control Pressure...52 Injector Disable...54 Relative Compression...55 Air Management...57 Boost Control...60 Torque Converter Stall...63 Crankcase Pressure...64 Test Drive...68 Conclusion...71

2 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics MODULE I INTERNATIONAL VT 275 ENGINE PROGRAM II Introduction The following program demonstrates VT 275 Engine Hard Start/No Start and Performance Diagnostic procedures. This program is second in a series of training programs on the VT 275 Engine. The test procedures outlined in this program are designed to reduce repair time, increase up time, and maximize customer satisfaction. The test procedures outlined in this program are designed to reduce repair time, increase up time, and maximize customer satisfaction. Be sure that you have completed the first DVD and study guide in the series entitled, VT 275 Engine Introduction before starting the following program. The DVD and study guide are divided into three modules. The first module provides an Introduction. The second module covers Hard Start/No Start Diagnostics, and, the third module covers Performance Diagnostics. Consult current service literature prior to conducting any service or diagnostic work.

Study Guide 3 Before beginning the diagnostic process, be aware that diagnostic procedures WON T work effectively if any step is skipped or omitted. When the results of a test show a problem exists, the problem must be corrected. After it is corrected, the remaining diagnostics DON T need to be completed. As we review these VT 275 Engine repair procedures, keep in mind that proper service techniques, environmental concerns and safety are the most important parts of the process. Perform service inside a well-ventilated, dry shop. Make sure the vehicle is parked on a flat service with the parking brake set and the wheels blocked. Perform service inside a wellventilated, dry shop. Be sure that you know the location of properly rated and charged fire extinguishers. When working on the engine, keep the work area and tools as clean as possible. Also, clean all connections or fittings before disconnecting or removing components. Use a suitable pan to catch any fluid when disconnecting components. Wear safety glasses and chemical blocking nitrile gloves when performing work of any kind.

4 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics When performing actual diagnostics, it is important to obtain a diagnostics form and record all of the test results on the Diagnostics Form. Specifications for the tests are not pre-printed on the form. Instead they must be transferred to the form from the Performance Specification section of the Diagnostics Manual on ISIS. Be sure to follow each warning, caution, and note as they are presented throughout this training program. Be sure to follow each warning, caution, and note as they are presented throughout this training program. Warnings indicate procedures and safety measures that must be followed precisely to avoid personal injury or death to yourself or other shop personnel, and to avoid damage to the vehicle, equipment or components. Cautions indicate a procedure that you must follow exactly to avoid equipment or component damage. Notes indicate operations, procedures or instructions that are important for proper service. The DVD program also includes a new interactive glossary, to help you learn more about technical terms at your own discretion. This feature allows you to interrupt program playback and learn more about a specific technical term.

Study Guide 5 Then the feature allows you to resume the program where you left off. Whenever you would like to know more about a particular term, press the top menu or title key. Then choose glossary. Then navigate through the glossary listings as needed to select the desired term. Once the term is defined, the glossary menu will reappear automatically. If you d like to view another definition, simply select it. If you want to return to the program where you left off, select the resume program button. If you want to return to the program where you left off, select the resume program button.

6 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 7 NOTES

8 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics MODULE II HARD START/NO START DIAGNOSTICS Initial Ignition Key-On Some faults that could be detected in this test are: No key power to the ECM or IDM A failed ECM or IDM relay Faulty power or ground circuits A failed ECM or IDM An inoperative fuel pump The ECM detects water in the fuel An inoperative CAN 2 link The initial ignition Key-On test verifies that the ECM and IDM have power, the fuel pump has power and the ECM hasn t detected water in the fuel. The initial ignition Key-On test verifies that the ECM and IDM have power, the fuel pump has power and the ECM hasn t detected water in the fuel. A quick indicator of ECM power is the wait-to-start lamp. Turn the key switch to the ON position. Watch for the wait-to-start lamp. If the lamp comes on before the dash lamp self-test, the ECM has power. If the lamp does NOT come on, verify power to the ECM by going directly to Step 11 of the Diagnostics Form. Once power to the ECM is verified, return to this step in hard start/no start diagnostics.

Study Guide 9 A quick indicator of IDM power is the injector pre-cycle. Turn the key to the ON position, and listen for the pre-cycle sound. If the pre-cycle occurs, the IDM has power. A quick indicator of IDM power is the injector pre-cycle. If the pre-cycle does NOT occur at Key-On, verify power to the IDM by going directly to Step 12 of the diagnostics form. Once power to the IDM is verified, return to this step in hard start/no start diagnostics. If there is power to the IDM, but there is still no pre cycle, verify that the CAN 2 link is working. If it is, the IDM may have failed. Next, monitor the water-in-fuel lamp. If the lamp comes on, remove the plug from the fuel pump module and allow the fuel to drain. Replace the drain plug. Turn the key ON and allow the pump module to refill. Recheck the dash lamp. If the lamp is still ON, go directly to Test 10 to take a fuel sample.

10 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Engine Cranking Some faults that could be detected in this test are: A discharged battery No key power to the ECM A starting system failure A circuit fault for Engine Crank Inhibit (ECI) Mechanical engine damage The purpose of the engine cranking test is to determine if cranking RPM is sufficient to start the engine. The purpose of the engine cranking test is to determine if cranking RPM is sufficient to start the engine. Crank the engine while reading the dash gauges. Record the tachometer reading on the Diagnostics Form. Compare the tachometer reading against cranking performance specifications. If the engine speed does not meet the cranking specification, use the Truck Diagnostic Manual to diagnose the batteries and cranking system before attempting any further hard start/no start diagnostic tests.

Study Guide 11 Diagnostic Trouble Codes Some faults that could be detected in this test are: An electronic failure A failure of the ICP sensor or ICP system A failure of the Air Management System A faulty pressure or temperature sensor Glow plug or inlet air heater failure The purpose of this step is to fill out the heading of the Diagnostics Form, extract any starting related DTCs, and, to determine the Key-On Engine-Off signal values of the temperature and pressure sensors. With the EZ-Tech, select the VIN+ icon. Using the information generated on the screen, fill out the heading section of the Hard Start/No Start Diagnostics Form. Be sure to fill out the miles, hours, VIN, ambient temperature, coolant temperature, engine serial number, engine horsepower, engine family rating code, and ECM/IDM calibration. The purpose of this step is to fill out the heading of the Diagnostics Form, extract any starting-related DTCs, and to determine the Key-On Engine-Off signal values of the temperature and pressure sensors.

12 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics ENGINE FACT: Fill in the turbocharger number and injector number only when incompatible components are suspected. Then, record all active and inactive DTCs. Determine the cause of all active codes and make all repairs as needed before continuing. Next, clear all DTCs. Finally, record the Key-On Engine- Off or KOEO temperature sensor signal values if all the sensor readings are NOT within 5 degrees of each other. Also record the ICP signal value if it fluctuates more than 50 psi. Next, record the manifold absolute pressure signal value if it fluctuates more than 1 psi. Record the barometric absolute pressure value if it is different from other International vehicles at your location with Diamond Logic Control 2. If the EZ-Tech is not available, DTCs can be extracted by reading dash warning light flash sequences. These sequences are initiated by pressing and releasing the cruise ON and resume/accel switches at the same time, twice within 3 seconds of Key-On.

Study Guide 13 Refer to the Engine Diagnostic Manual for an explanation on how to read and interpret these flash codes. Key-On Engine-Off (KOEO) Standard Test Some faults that could be detected in this test are: The following relays: intake air heater, fuel pump, and glow plug. The electrical circuit of the injection pressure regulator valve Use MasterDiagnostics software to perform the Key-On Engine-Off Standard Test. When the test is over, the diagnostic trouble code screen will show DTCs if there is a problem. Record all DTCs on the Hard Start/ No Start Diagnostics Form. Fix these faults before going to the next step. Record all DTCs on the Hard Start/No Start Diagnostics Form. Finally, clear all DTCs.

14 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics KOEO Injector Test Some faults that could be detected in this test are: An open or shorted injector wiring harness A bad wiring harness connection on the injector coil A defective injector coil A failed ECM or IDM When using MasterDiagnostics to run any Key-On Engine-Off or Key- On Engine-Running test, the standard test must always be selected and run first. This must be done after each key cycle. Use MasterDiagnostics to perform the Key-On Engine-Off Injector Test. The injector test determines if the injector coils and the injector circuits are working properly by monitoring the circuits during test operation. The injector test determines if the injector coils and the injector circuits are working properly by monitoring the circuits during test operation. The technician should be able to hear audible clicks for each injector. Non-clicking injectors may indicate a problem in the spool valve of that injector. Note that cold temperatures or thick oil may dampen the noise so that it cannot be heard.

Study Guide 15 When the test is completed, record any DTCs on the Hard Start/No Start Diagnostics Form. Correct any problems causing active DTCs. Finally, clear the DTCs. EST Data List Some faults that could be detected in this test are: Low cranking speed Low lube oil pressure Low ICP pressure A stuck EGR valve Open the Hard Start/No Start session in the MasterDiagnostics software. Monitor the engine s parameters while cranking the engine for 20 seconds. Check and record the following on the Diagnostics Form: battery voltage, RPM, injection control pressure, engine oil pressure, and EGR valve position. If the battery voltage drops below 7 volts, the ECM will not stay powered up. If engine cranking is too low, there might not be enough speed to create the compression to ignite the fuel. Check and record the following on the Diagnostics Form: battery voltage, RPM, injection control pressure, engine oil pressure, and EGR valve position.

16 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics If the EZ-Tech shows 0 RPM during cranking, the ECM may not be receiving a signal from the crankshaft or camshaft sensors. Be sure to crank for at least 20 seconds. Then check for DTCs. If MasterDiagnostics indicates low or no injection control pressure, go to Test 13: Low ICP System Pressure. If oil pressure is low, the injection control pressure system may not be receiving enough oil. NOTE: VT 275 engines are equipped with an oil pressure switch. On production engines, when oil pressure is low, MasterDiagnostics will show an engine oil pressure of 0 psi. When pressure is normal, MasterDiagnostics will show an engine oil pressure of 25 psi. Use the oil pressure test coupler, ZTSE4526 and the gauge bar to measure the pressure. Go to Symptom Diagnostics in the Diagnostics Manual on ISIS. If the EGR valve is open, go to EGR Control in Electronic Control System Diagnostics in the Diagnostics Manual on ISIS. As an alternative, engine oil pressure can be measured at the lube oil pressure test port. First, remove the engine oil pressure switch. Then install the test fitting, ZTSE4552. Use the oil pressure test coupler, ZTSE4526 and the gauge bar to measure the pressure. Monitor engine oil pressure while cranking the engine for 20 seconds.

Study Guide 17 Engine Systems Some faults that could be detected in this test are: Faulty sensor connections Damaged or incorrectly installed electronic connectors Leakage in the air induction system The visual inspection process is critical. Look specifically at the IPR valve, camshaft sensor, and crankshaft sensor to be sure they are properly connected. Look at the electronic control system including the ECM and IDM power connections and fuses. Make sure the connections aren t corroded. Check for the following: Check the air induction system for leaks. Check the fuel system including the tank and lines; look for damage or leaks. Inspect the engine for large oil or coolant leaks that may indicate mechanical damage.

18 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 19 NOTES

20 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Engine Oil Some faults that could be detected in this test are: Low oil level through consumption or incorrect service High oil level caused by incorrect service, fuel in the oil, or coolant in the oil With the vehicle parked on level ground, check the oil level. NOTE: Oil diluted with long-life coolant may turn gray instead of white and may increase in viscosity. With the vehicle parked on level ground, check the oil level. At the same time, inspect the lube oil for contaminants, such as fuel or coolant. Also, keep in mind that the oil viscosity must match the requirements for the ambient temperature in which the vehicle operates. If coolant is leaking into the engine, the engine oil may become milky white or the oil viscosity will increase. If fuel is entering the crankcase, the oil will be diluted and take on the smell of diesel fuel and the crankcase oil level may become overfilled.

Study Guide 21 Intake and Exhaust Restriction Some faults that could be detected in this test are: Foreign material blocking the air cleaner inlet Tailpipe or muffler damage A restricted catalytic converter A restricted air filter element Check the filter minder. When the gauge indicator is locked at high restriction, the filter element is blocked and must be replaced. Check for restrictions in the intake system. A restriction that reduces intake air volume can cause a hard start/no start condition. A partial restriction can also cause a loss in power. Inspect the air inlet system for damage. The air inlet and hood ducting should not be blocked or damaged. Inspect the entire exhaust system for kinked pipes, and damaged mufflers. A restriction in the exhaust system may cause performance problems or may even result in a hard start/no start condition. Check for restrictions in the intake system.! WARNING: To avoid serious personal injury, be sure the exhaust system is cool before inspecting components.

22 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 23 NOTES

24 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Fuel Supply System Some faults that could be detected in this test are: Contaminated fuel, aerated fuel, or debris in the tank A crimped or blocked fuel line A clogged or cracked pick-up tube A restricted fuel filter An inoperative fuel pump A faulty fuel pressure regulator Required Tools: 0 160 psi gauge (on gauge bar tool) ZTSE4409 ICP system test adapter ZTSE4594 In-line shut-off valve 3/8 inch clear sample line Clear container with a wide opening (approximately 1 liter or 1 quart) The pump should run for 60 seconds. After 60 seconds the ECM turns the fuel pump OFF unless the engine is running. Check the level in the fuel tanks. Turn the ignition switch to ON and check the fuel pump for operation. The pump should run for 60 seconds. After 60 seconds the ECM turns the fuel pump OFF unless the engine is running. The pump relay and pump operation can be activated using the

Study Guide 25 MasterDiagnostics Key-On Engine-Off Output State Test. Toggling the output low should activate the relay and operate the pump. You should be able to hear or feel the pump running. The ECM monitors fuel pump relay operation with a diagnostic circuit from the normally open terminal of the relay to the ECM. If the relay is ON, MasterDiagnostics should show the fuel pump monitor value as ON. During engine operation, if the diagnostic circuit does NOT show the correct value when the relay should be ON, the ECM will set a diagnostic trouble code, or DTC. The ECM monitors fuel pump relay operation with a diagnostic circuit from the normally open terminal of the relay to the ECM. Keep in mind that this engine could run even if the fuel pump does not come on, but it will have low power under load. Do not assume the fuel pump is running just because the engine is running. Fuel pressure can be measured at the secondary fuel filter housing. Remove the test port plug. Install pressure gauge ZTSE4681 and test adapter ZTSE4594 to the secondary fuel filter housing.

26 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Turn the key switch to the ON position and measure the fuel pressure. The measured pressure is after the secondary filter. The fuel pressure should be a minimum of 50 psi If fuel pressure does not meet the minimum, verify there is fuel in the tank, that the pump is running, and then, if needed, replace the primary and secondary fuel filters. Fuel aeration can be detected visually using the fuel pressure gauge ZTSE4681. Fuel aeration can be detected visually using the fuel pressure gauge ZTSE4681. With the gauge installed and the key switch ON, open the valve to allow fuel to flow into a clean container. Observe the fuel flow. Opening the system to install the hose will allow some air to enter the system. This air will be visible in the fuel flow initially, but should clear within a few seconds. If the fuel continues to show signs of aeration, check the suction side of the system, from the fuel tank to the pump inlet, for air leaks. If the fuel pressure is low and the filters are good, isolate the fuel pump to check its ability to create pressure.

Study Guide 27 Remove the banjo bolt on the pressure line at the secondary fuel filter. Do not reuse the copper washers to replace the bolt. Insert the bolt through the line fitting and attach the pump output test adapter, ZTSE4696. Attach a 0 150 psi fuel pressure gauge to the test adapter. The fuel pump and its internal pressure relief valve are now isolated from the engine mounted fuel system components. Turn the key switch to the ON position and measure the fuel pressure while the pump is running. The discharge pressure of the pump is typically 80 psi. The fuel pump and its internal pressure relief valve are now isolated from the engine mounted fuel system components. If the pump pressure meets specifications, remove the fuel filter housing from the oil filter assembly. Then remove the pressure regulator. Check the regulator for debris or damage. If the pressure is well below specifications, check for damaged fuel lines and high pump inlet restriction.

28 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics High inlet restriction can starve the suction side of the fuel pump and cause low fuel pressure. With the key switch OFF, remove the fuel pump module water drain plug. The drain is located on the outside of the left frame rail. Install the fuel inlet restriction adapter, ZTSE4698, in place of the plug. Connect the 0-30 inches of mercury pressure gauge, through a closed shutoff valve, to the adapter. Both the valve and the gauge are part of the ZTSE4409 gauge bar kit. Turn the key switch ON. With the fuel pump running, open the valve and record the gauge reading. If inlet restriction causes a gauge reading of greater than 6 inches of mercury, check the lines from the fuel tank to the pump for restrictions. If the pump CANNOT produce the correct pressure, and there are no restrictions between the tank and the pump, the pump is defective.

Study Guide 29 If the fuel system will not prime, and has pulsating fuel pressure, go to Combustion Leaks to Fuel in Section 4: Engine Symptom Diagnostics on ISIS. Document your findings on the Hard Start/No Start Diagnostics Form. Main Power Relay Voltage to ECM Document your findings on the Hard Start/No Start Diagnostics Form. Some faults that could be detected in this test are: A discharged battery Faulty battery cable connections A faulty ECM relay With the key switch OFF, remove the two white connectors, 3 and 4 from the ECM. Install the breakout box connectors 3 and 4 to the connections on the ECM. Measure the voltage with the positive lead on connector 4 pin 2 and the negative lead on connector 3 pin 7. Crank the engine for 20 seconds. Next, measure the voltage with the positive lead on connector 4 pin 1 and the negative lead on connector 3 pin 6.

30 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Crank the engine for 20 seconds once again. If either voltage is below 7 volts consult Electronic Control Module Power in Section 7 of the Diagnostics Manual for further diagnostic steps, and repair any problems as needed. If either voltage is below 7 volts consult Electronic Control Module Power in Section 7 of the Diagnostics Manual for further diagnostic steps, and repair any problems as needed. Main Power Relay Voltage to IDM Some faults that could be detected in this test are: Faulty battery cable connections A faulty IDM relay A faulty connection at the engine to chassis twelve-way connector With the key switch OFF, separate the 12-way engine-to-chassis connector. Install the 12 pin breakout harness. Connect the positive lead of the digital multimeter to pin 12 and the negative lead to pin 1. Crank the engine for 20 seconds and measure the voltage. Next, move the positive lead to pin 6.

Study Guide 31 Crank the engine again for 20 seconds and measure the voltage. If either voltage is below 7 volts, refer to IDM Power and Ground Diagnostics in the Electronic Control System section of the Diagnostics Manual for further diagnostic steps, and repair any problems as needed. Low ICP System Pressure Some faults that could be detected in this test are: An ECM that is not controlling the IPR An inoperative IPR A leak in the high-pressure system Low oil level in the reservoir Or an inoperative high-pressure pump If either voltage is below 7 volts, refer to IDM Power and Ground Diagnostics in the Electronic Control System section of the Diagnostics Manual for further diagnostic steps, and repair any problems as needed. Required Tools: EZ-Tech with MasterDiagnostics software EZ-Tech interface cable Digital multimeter Actuator breakout harness ZTSE4484 Pressure sensor breakout harness ZTSE4347 Oil fill extension 180971C91

32 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics ICP system test adapter ZTSE4594 ICP leak test plug ICP sensor adapter (tool kit ZTSE4690) The Injection Control Pressure System must be able to build a minimum of 500 psi during cranking for the engine to start. The Injection Control Pressure System must be able to build a minimum of 500 psi during cranking for the engine to start. The following tests can be used to diagnose an engine no start caused by low injection control pressure. The tests must be performed in the correct order to be valid. Refer to the Service Manual on ISIS for the step-by-step procedures. The possible causes of low ICP during cranking are: If the ICP is low while cranking, verify the engine has met the minimum cranking lube oil pressure of 20 psi. A low oil level in the reservoir A faulty IPR electrical circuit The ECM is not controlling the IPR An inoperative IPR A leak in the high-pressure system An inoperative high-pressure pump If the ICP is low while cranking, verify the engine has met the minimum cranking lube oil pressure of 20 psi. Inspect the IPR connector for corrosion.

Study Guide 33 During cranking, the ECM must command the IPR valve to close partially and create the pressure required for starting. Test this function by replacing the ECM signal with a direct connection between the IPR, power and ground. Disconnect the IPR from the engine harness. Install the actuator breakout harness to the IPR. Do NOT connect it to the engine harness. Use jumper wires to provide power to one lead and a ground to the other. Crank the engine while monitoring the injection control pressure on MasterDiagnostics. Install the actuator breakout harness to the IPR. Do NOT connect it to the engine harness. If the engine starts or the pressure now exceeds the minimum cranking pressure, the ECM was not controlling the IPR prior to doing this test. The IPR must function for the ICP system to build sufficient pressure to start. To test the IPR for operation, remove the ICP sensor from the right bank valve cover.

34 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics! CAUTION: Do not leave the IPR powered for more that 120 seconds, or the IPR may be damaged.! CAUTION: Install a shut-off valve in line with the shop air hose. Make sure that the shut-off valve is closed before connecting the shop air hose to the high pressure rail. This will prevent oil from blowing out of the air fitting. Install the ICP system test adapter with an air fitting in place of the sensor. Remove the oil fill cap and connect shop air pressure to the air fitting. The system is built to withstand 4,000 psi shop pressure will NOT damage the system. Listen at the opening of the oil fill cap for air leaking into the crankcase from the IPR. Allow five minutes for the air to displace the oil through the system cold oil may take longer. If a massive air leak is heard, go directly to the Under Valve Cover Leak Test. If there is a faint leak, install the actuator breakout harness to the IPR. Again, do not connect it to the engine harness. Provide power to one breakout harness lead and a ground to the other. The faint air leak in the crankcase should stop when power is applied. The faint air leak in the crankcase should stop when power is applied. If the faint air leak stops, go directly to the pump test. If the faint air leak does not stop, replace the IPR and retest.

Study Guide 35 If the IPR function test reveals a massive air leak, remove the valve covers and apply shop air pressure to the ICP system test adapter. Attempt to isolate the the leak. The possible leak points are: The rail to injector O-rings The rail fittings The case-to-head tube and port plug O-rings The branch tube assembly The pump housing If the air leak cannot be detected in the valve cover area, remove the caseto-head tubes, and inspect the lower O-rings. If the O-rings are split or damaged the case-to-head tube must be replaced. If the O-rings are good, remove the high-pressure pump cover. Connect shop air, and listen for the air leak at the pump-to-branch tube connections. If the O-rings are split or damaged the case-to-head tube must be replaced. If the location can NOT be detected, isolate each bank and test. To test the left bank, install the ICP leak test plug from the ZTSE4690 tool kit. Put the test plug in place of the port plug.

36 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Make sure the IPR is connected. Crank the engine while measuring the ICP. If the engine starts or ICP exceeds 500 psi, the leak causing the low ICP is in the left bank. Remove the ICP leak test plug from the left bank, and reinstall the port plug. To test the right bank, install the ICP sensor adapter from the ZTSE4690 tool kit, in place of the right bank rear port plug. Install the ICP sensor in the top of the adapter and connect it using the three-wire sensor breakout harness as an extension. Crank the engine while measuring ICP. If the engine starts or the ICP exceeds 500 psi, the leak causing the low ICP is in the right bank. Crank the engine while measuring ICP. If the engine starts or the ICP exceeds 500 psi, the leak causing the low ICP is in the right bank. If the engine does NOT start, or ICP is still low, complete the High Pressure Pump Test. The pump can be deadheaded by installing the ICP leak test plug in place of the left bank rear port plug and the ICP sensor adapter in place of the right bank rear port plug.

Study Guide 37 Install the ICP sensor in the top of the adapter, and connect it using the three-wire sensor breakout harness. Leave the valve covers off. Crank the engine while measuring ICP. If the ICP exceeds 500 psi, the pump is NOT at fault, and there is a leak in the system. Install the ICP sensor in the top of the adapter and connect it using the three-wire sensor breakout harness as an extension. If the pressure is below the minimum cranking pressure, and there are no leaks around the pump, remove the pump from the crankcase. Oil should come up from the pump feed port in the crankcase indicating that the reservoir has oil. If the reservoir has oil, the pump is inoperative.

38 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 39 NOTES

40 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Glow Plug System Some faults that could be detected in this test are: A defective glow plug relay A defective glow plug A defective wiring harness Required Tools: Fluke 88 ZTSE4357 Amp clamp ZTSE4575 Glow plug test lead ZTSE4568 Install a current clamp around the feed wire for the glow plugs on the right bank. NOTE: The Key-On Engine-Off Standard Test must be run before running the Glow Plug Output State Test. Install a current clamp around the feed wire for the glow plugs on the right bank. Turn the key switch ON but don t start the engine. Using MasterDiagnostics, run the Inlet Air Heater/Glow Plug Output State Test. Be aware that this test is limited to two requests per key cycle. After 40 seconds, record the amperage reading for the right bank. Now, install the current clamp around the feed wire for the glow plugs on the left bank and repeat the test.

Study Guide 41 The draw for each bank should be 22 42 amps. If both readings are zero amps, use a digital multi meter to verify that the normally open terminal of the glow plug relay has battery voltage when the test is running. The draw for each bank should be 22 42 amps. If either amperage reading is low, pull the individual glow plug wires from the loom. Then restart the Output State Test. After 40 seconds, use the amp clamp to measure the amperage draw on each individual wire. An individual glow plug wire should draw 8 to 10 amps. After locating any wire that does not meet specifications, refer to the steps in the glow plug section of Hard Start/ No Start Diagnostics located in the Diagnostics Manual on ISIS. Inlet Air Heater Some faults that could be detected in this test are: A defective inlet air heater relay A defective inlet air heater element Or, a defective wiring harness

42 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Required Tools: Fluke 88 ZTSE4357 Amp clamp ZTSE4575 Install the amp clamp around the feed wire to the Inlet Air Heater element. Turn the key switch ON, but DON T start the engine. Using MasterDiagnostics, run the Inlet Air Heater/Glow Plug Output State Test. Remember that this test is limited to two requests per key cycle. After five seconds, measure the amperage reading and record the results. If the amperage reading is less than the 45 55 amp specification, use the digital multimeter to measure the voltage at the inlet heater element connector. If the amperage reading is less than the 45 55 amp specification, use the digital multimeter to measure the voltage at the inlet heater element connector. If the meter reading is approximately equal to the battery voltage, the heater element is faulty. If the meter reading is less than battery voltage, the inlet air heater relay is inoperative or there is high resistance in the circuit.

Study Guide 43 Check each circuit component for opens or high resistance and repair as needed. Refer to the Inlet Air Heater section of Electronic Diagnostics for further diagnostic tests. Check each circuit component for opens or high resistance and repair as needed.

44 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 45 NOTES

46 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics MODULE III PERFORMANCE DIAGNOSTICS Performance Diagnostics has fifteen steps or sections to be performed when diagnosing a performance complaint. The first six tests are identical to six tests already covered within the hard start/no start diagnostics portion of this program; therefore, these tests are only covered in brief. All tests should be done in the order that they are presented on the form. All tests should be done in the order that they are presented on the form. When performing these tests, record the results on the Diagnostics Form. Again, this module shows the technician how to perform each of these steps. Diagnostic Trouble Codes The KOEO Standard Test is the same as Test 4 in hard start/no start diagnostics. This test is the same as Test 3 in hard start/no start diagnostics. When performing this test, you will use the EZ Tech to check for diagnostic trouble codes and complete the information header on the Diagnostic Form. Repair any active codes before continuing. KOEO Standard Test The KOEO Standard Test is the same as Test 4 in hard start/no start diagnostics. When performing this test,

Study Guide 47 use the EZ Tech to determine if there are any electrical malfunctions detected by the ECM self-test and output circuit check. KOEO Injector Test The KOEO Injector Test is the same as Test 5 in hard start/no start diagnostics. When performing this test, use the EZ Tech. The purpose of this test is to determine if the electrical portion of each fuel injector is working. Engine Oil The Engine Oil Test is the same as Test 8 in hard start/no start diagnostics. Determine the oil level and oil quality. Both affect injector operation. Fuel The Fuel Test is the same as Test 5 in hard start/no start diagnostics. During this test, use the fuel pressure gauge to check the fuel supply system for aeration, contamination, and pressure. Intake and Exhaust Restriction The Intake and Exhaust Restriction Test is the same as Test 9 in hard start/ no start diagnostics. The Intake and Exhaust Restriction Test is the same as Test 9 in hard start/no start diagnostics.

48 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Check the engine for high intake and exhaust restriction. KOER Standard Test! WARNING: To avoid serious personal injury, be sure the exhaust system is cool before inspecting components. Some faults that could be detected in this test are: An oil leak in the high pressure injection control system A loose or corroded wiring harness to the ICP sensor or IPR valve A defective ICP sensor or IPR valve A defective high pressure pump The Key-On Engine Running Standard Test verifies that the Injection Control Pressure System is operating correctly. If a problem exists and it is detected during this test, a DTC will be set. Open the KOER Standard session to monitor engine operation. Then, start the engine and let it run until the engine coolant temperature reaches at least 158ºF (70 C). Use MasterDiagnostics to run the KOER Standard Test. First, during the test, the ECM commands the IPR to increase the injection control pressure.

Study Guide 49 The ECM monitors the actual pressure and compares it to the desired increased value. Second, the ECM commands the IPR to decrease the injection control pressure. The ECM monitors the actual pressure and compares it to the desired decreased value. If the ECM detects a problem, a DTC is set. The ECM monitors the actual pressure and compares it to the desired increased value. Go to the Injection Control Pressure section of Electronic Control System Diagnostics in the Engine Diagnostics Manual on ISIS for further diagnostic tests. Record all DTCs, correct any problems, and clear the DTCs once the problems are corrected.

50 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics NOTES

Study Guide 51 NOTES

52 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Injection Control Pressure Some faults that could be detected in this test are: Poor quality oil, or oil not serviced at the correct intervals ICP system leakage A failed ICP sensor or sensor circuit A failed IPR valve A failed high-pressure oil pump A failed oil pick up tube A missing or failed gasket for the oil pick up tube Required Tools: EZ-Tech with MasterDiagnostics software EZ-Tech interface cable Run the engine at low idle and monitor the ICP. Record the idle value on the diagnostic form and compare the results with the specification. Run the engine at low-idle and monitor the ICP. Record the idle value on the diagnostic form and compare the results with the specification. Now run the engine at high-idle. Hold the engine at high-idle for a few seconds to allow the injection control pressure to stabilize. Record the value on the form. Now run the engine at high-idle for two minutes. Monitor the pressure, and record the two minute results on the diagnostic form.

Study Guide 53 Compare the two pressure readings. Readings that rise above the specification or are unstable at any point during the test could indicate oil aeration. To test for aeration, install the fuel pressure test fitting in place of the engine oil pressure switch. Install the oil sample line. Make sure the shut-off valve is closed. Run the engine for two minutes at high-idle. Compare the two pressure readings. Readings that rise above the specification or are unstable at any point during the test could indicate oil aeration. Return the engine to low-idle, and take an oil sample in a clear container. Check for foam. If the oil is aerated with a large quantity of air bubbles, recheck the oil level to be sure it is NOT over full. Also, air leaks on the suction side of the lubrication system can cause aeration. Correct the condition before continuing. If the pressure was out of specification at high-idle but not aerated, disconnect the ICP sensor and check engine stability. If the problem is corrected, see ICP Operational Diagnostics in Section 7 of the Diagnostics Manual on ISIS. If the problem is corrected, see ICP Operational Diagnostics in Section 7 of the Diagnostics Manual on ISIS.

54 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics If ICP is still high or unstable, replace the IPR and retest. Injector Disable A fault that could be detected in this test is: A weak cylinder or cylinders This test, along with the Relative Compression Test, is used to distinguish between an injector problem or a mechanical problem when detecting the cause of a rough idle or performance problem. Start the engine. Select Sessions and choose Open. Select the KOER_IDT_V6 session. Then select Diagnostics from the menu bar. Now, select V6 Injector Disable Tests. Select auto run. This test will automatically disable one injector at a time and record the effect on the engine s total load and fuel usage. MasterDiagnostics will display the results of this test on the screen.

Study Guide 55 In the text view, compare each cylinder s fuel rate deviation with the cut-off value. Then compare all load deviation values with the cut-off value. Any cylinder in which both values are low is suspect for low contribution to the engine s power. If a suspect cylinder is identified, do Test 10, Relative Compression, to distinguish between an injector or a mechanical problem. Any cylinder in which both values are low is suspect for low contribution to the engine s power. Relative Compression Some faults that could be detected in this test are: Piston damage Loose injectors Leaking or bent valves Bent connecting rods Bent pushrods The relative compression test evaluates the base engine condition. During this test the ECM measures the engine cranking speed for each cylinder just before Top Dead Center or TDC on the compression stroke and 30 degrees after TDC on the power stroke.

56 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics On a cylinder with good compression, the crankshaft will slow down as the piston pushes against compression. On a cylinder with good compression, the crankshaft will slow down as the piston pushes against compression. It will speed up as it passes TDC and begins the power stroke. This will NOT occur with a poor cylinder. After the test is completed, the numbers that appear on the screen for each cylinder are the difference between the crankshaft speed at 30 degrees after TDC and just before TDC on the compression stroke. To do the test, the batteries must be fully charged. Using MasterDiagnostics, select the Relative Compression Test from the drop down menu. Turn the ignition key ON. When a message appears that says Stop Cranking Within Five Seconds stop cranking, but do NOT turn the key switch to the OFF position. Click run. Within five seconds of selecting run, crank the engine and continue for 15 seconds. When a message appears that says Stop Cranking Within Five Seconds stop cranking, but do NOT turn the key switch to the OFF position.

Study Guide 57 The six relative compression values that result from the test should be compared with one another. If a value is zero or much lower than others, then check for a mechanical problem. If any value is 255, then the results are NOT valid and the test will need to be repeated. If both the Relative Compression Test and the Injector Disable Test identify the same suspect cylinder, check for a mechanical problem, such as low compression or a bent push rod. If the Relative Compression Test does not identify a suspect cylinder, but the Injector Disable Test does, replace the suspect injectors. Air Management Some faults that could be detected in this test are: An exhaust leak before the turbocharger A leak in the intake system after the mass air flow sensor The mass air flow sensor is defective The turbocharger is defective The EGR valve is defective The EGR valve drive module is defective The catalytic converter is plugged

58 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics Required Tools: EZ-Tech with MasterDiagnostics software EZ-Tech interface cable The purpose of the Air Management Test is to check the Air Management System and the Exhaust Gas Recirculation valve. The purpose of the Air Management Test is to check the Air Management System and the Exhaust Gas Recirculation valve. During the Air Management Test, the ECM will monitor the effects of EGR valve movement using the Mass Air Flow sensor. If a problem is detected, the ECM will cancel the test, set a DTC, and restore normal engine operation. Open the KOER_Air Management_ V6 session to monitor engine operation. Select Diagnostics from the menu bar. Select Key-On Engine-Running Tests from the drop down menu. From the KOER Diagnostics menu, select Air Management, and select Run to start the test. The ECM commands the EGR valve to close and increases the engine speed to 900 RPM.

Study Guide 59 The ECM expects the mass air flow to increase. Then the ECM commands the EGR valve to open and expects flow to decrease. The ECM expects the mass air flow to increase. Finally, the ECM commands the EGR valve to close once again. As before, flow is expected to increase. Then, the ECM returns the EGR valve and engine idle speed to normal operation. During this test, when the EGR valve is closed, the engine must achieve a mass air flow of 3.8 lbs per minute for the test to pass. When the EGR valve is open, the mass air flow must be less than 2.97 lbs. per minute to pass. If any mass air flow does not match expectations during the tests, DTC 346 is set, and the test is cancelled. If a test cancels, repeat the test, follow the graphic screen display, and determine whether the test is cancelled when the EGR valve is commanded to be closed or when it is commanded to be opened. If any mass air flow does not match expectations during the tests, DTC 346 is set and the test is cancelled.

60 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics This may assist in further diagnostic testing. Although the ECM is controlling the EGR valve during this test, keep in mind the mass air flow through the engine can be affected by the following: A leak before the turbocharger A leak in the intake system after the mass air flow sensor A defective mass air flow sensor A defective turbocharger A defective EGR valve A defective EGR drive module A plugged catalytic converter Boost Control Some faults that could be detected in this test are: A leaking pneumatic actuator Broken, cracked, or disconnected tubing A failed boost control solenoid A faulty circuit to the boost control solenoid Required Tools: EZ-Tech with MasterDiagnostics software EZ-Tech interface cable Gauge bar tool ZTSE4409

Study Guide 61 Vacuum pump and gauge ZTSE7559 Marker The purpose of the Boost Control Test is to verify that the turbocharger bypass control valve is operating correctly. Use thin nose pliers to check the movement of the pneumatic actuator linkage. The purpose of the Boost Control Test is to verify that the turbocharger bypass control valve is operating correctly. If the actuator will not move, disconnect the linkage and determine if either the pneumatic actuator or the bypass valve is stuck. Repair as needed. Next, test to verify that the actuator moves the linkage with the following steps. First, mark a reference spot on the linkage shaft. Then, disconnect the tube from the manifold elbow. Attach the gauge bar tool to the tube in its place. Using the gauge bar tool hand pump, apply pressure to the pneumatic actuator. As pressure starts to build up, linkage movement should begin at 15 psi. Make sure that you do not exceed 30 psi.

62 International VT 275 Engine, Program II: Hard Start/No Start & Performance Diagnostics If the hand pump is unable to build pressure, the system may have an air leak. If the hand pump is unable to build pressure, the system may have an air leak. Use a mixture of soap and water to coat the pneumatic actuator, the plastic tubing, and the boost control solenoid. Using the gauge bar tool hand pump, apply pressure to the pneumatic actuator to locate the leak. Repair as needed. If there are no leaks, but the actuator doesn t move during the test, then the hand pump should be connected directly to the pneumatic actuator. If the actuator now moves when pressure is applied, the boost control solenoid is defective. Turn the key switch ON. Using the gauge bar tool hand pump, apply 25 psi, not to exceed 30 psi, to the pneumatic actuator through the supply tube. The actuator rod should move. Select Diagnostics from the menu bar. Select Key-On Engine-Off Tests from the drop down menu. From the Key-On Engine-Off Diagnostics menu, select Output State Test High, and select Run. If the bypass valve linkage does NOT move to the closed position during the