1994 ENGINE PERFORMANCE TOYOTA SYSTEM & COMPONENT TESTING

Transcription

1 1 of 65 12/5/2014 1:13 PM 1994 ENGINE PERFORMANCE TOYOTA SYSTEM & COMPONENT TESTING INTRODUCTION Before testing separate components or systems, perform procedures in articles listed below: BASIC TESTING - 4-CYL BASIC TESTING - V6 Since many computer-controlled and monitored components set a diagnostic trouble code if they malfunction, also perform procedures in articles listed below: TESTS W/CODES - 4-CYL TESTS W/CODES - V Toyota Pickup 2.4L Eng Base NOTE: Testing individual components does not isolate shorts or opens. Perform all voltage tests with a Digital Volt-Ohmmeter (DVOM) with a minimum 10-megohm input impedance, unless stated otherwise in test procedure. Use ohmmeter to isolate wiring harness shorts or opens. NOTE: When testing some systems, tachometer may be required. Tachometer must be connected to proper terminals. For tachometer connections, see IDLE SPEED & MIXTURE in articles listed below: ADJUSTMENTS - 4-CYL ADJUSTMENTS - V6 COMPUTERIZED ENGINE CONTROLS ENGINE CONTROL MODULE Power & Ground Circuits For testing of power and ground circuits, see information in PIN VOLTAGE CHARTS article. See ECM LOCATION table for identifying ECM mounting locations. ECM LOCATION Model Pickup Location Behind Passenger's Side Kick Panel

2 2 of 65 12/5/2014 1:13 PM NOTE: For ECM terminal identification, see PIN VOLTAGE CHARTS article. ENGINE SENSORS & SWITCHES AIRFLOW METER NOTE: Airflow meter may be referred to as Volume Airflow (VAF) meter or Mass Airflow (MAF) meter. 1. Turn ignition off. Disconnect electrical connector from airflow meter. Note airflow meter terminal identification. See Fig 1 and Fig Using ohmmeter, measure resistance between specified terminals. See AIRFLOW METER RESISTANCE SPECIFICATIONS table. Replace airflow meter if resistance is not within specification. Fig 1: Identifying Airflow Meter Terminals (2.4L)

3 3 of 65 12/5/2014 1:13 PM Fig 2: Identifying Airflow Meter Terminals (3.0L) AIRFLOW METER RESISTANCE SPECIFICATIONS Application & Terminals Ohms 2.4L E1-FC Measuring Plate Fully Closed No Continuity Measuring Plate Other Than Closed 0 E2-VC E2-VB E2-THA -4 F (20 C) 10,000-20, F (0 C) F (20 C) F (40 C)

4 4 of 65 12/5/2014 1:13 PM 140 F (60 C) E2-VS Measuring Plate Fully Closed Measuring Plate Fully Opened L E1-FC Measuring Plate Fully Closed No Continuity Measuring Plate Other Than Closed 0 E2-VC E2-THA -4 F (20 C) 10,000-20, F (0 C) F (20 C) F (40 C) F (60 C) E2-VS Measuring Plate Fully Closed Measuring Plate Fully Opened COLD START INJECTOR TIME SWITCH 1. Ensure ignition is off. Disconnect electrical connector from cold start injector time switch. 2. Cold start injector time switch is located in engine coolant passage near cylinder head or thermostat housing. To verify wire colors for proper identification, see appropriate wiring diagram in WIRING DIAGRAMS article. NOTE: Cold start injector time switch may also be identified using appropriate illustration in THEORY/OPERATION article. 3. Note cold start injector time switch terminal identification. See Fig 3. Using ohmmeter, measure resistance at designated switch terminals at specified temperature. See COLD START INJECTOR TIME SWITCH RESISTANCE SPECIFICATIONS table. Replace cold start injector time switch if resistance is not within specification. COLD START INJECTOR TIME SWITCH RESISTANCE SPECIFICATIONS Application & Terminals Temperature Ohms 2.4L

5 5 of 65 12/5/2014 1:13 PM STA-STJ Less Than 50 (10) " Greater Than 86 (30) STA-Ground NA L STA-STJ Less Than 50 (10) " Greater Than 77 (25) STA-Ground NA Fig 3: Testing Typical Cold Start Injector Time Switch COOLANT TEMPERATURE SENSOR Coolant temperature sensor may be referred to as engine coolant temperature sensor. See ENGINE COOLANT TEMPERATURE (ECT) SENSOR under ENGINE SENSORS & SWITCHES. EGR GAS TEMPERATURE SENSOR

6 6 of 65 12/5/2014 1:13 PM NOTE: The EGR gas temperature sensor may be referred to as EGR function sensor. 1. Remove EGR gas temperature sensor from side of EGR valve. Place threaded end of sensor and thermometer in container of oil. 2. Attach ohmmeter to electrical terminals. Heat oil and note resistance at specified temperature. See EGR GAS TEMPERATURE SENSOR SPECIFICATIONS table. Replace EGR gas temperature sensor if resistance is not within specification. EGR GAS TEMPERATURE SENSOR SPECIFICATIONS Temperature F ( C) k/ohms 3.0L 122 (50) (100) (150) L 122 (50) (100) (150) 2-4 ENGINE COOLANT TEMPERATURE (ECT) SENSOR 1. Ensure ignition is off. Disconnect electrical connector from ECT sensor. The ECT sensor is located in engine coolant passage near cylinder head or thermostat housing. To verify wire colors for proper identification, see appropriate wiring diagram information in WIRING DIAGRAMS article. NOTE: The ECT may be also identified using appropriate illustration in THEORY/OPERATION article. 2. Using ohmmeter, check resistance between ECT sensor electrical terminals. Resistance should be within specification at designated temperature. See Fig 4. Replace ECT sensor if resistance is not within specification.

7 7 of 65 12/5/2014 1:13 PM Fig 4: Checking Engine Coolant Temperature Sensor KNOCK SENSOR 2.4L 4WD & 3.0L Information for testing of knock sensor is not available from manufacturer. If failure exists in knock sensor, diagnostic trouble code will be set in Engine Control Module (ECM). For diagnosis of knock sensor and circuit, see articles listed below: TESTS W/CODES - 4-CYL

8 8 of 65 12/5/2014 1:13 PM TESTS W/CODES - V6 PARK/NEUTRAL SWITCH NOTE: Park/neutral switch may be referred to as Park/Neutral Position (PNP) switch. A/T Models Disconnect electrical connector from park/neutral switch at transmission or transaxle. Note terminal identification. See Fig 5. Using ohmmeter, check for continuity at specified terminals with gearshift in proper positions. See PARK/NEUTRAL SWITCH SPECIFICATIONS table. Replace switch if defective. PARK/NEUTRAL SWITCH SPECIFICATIONS Application & Gearshift Position Park Reverse Neutral Drive Terminal Continuity "B" & "N", "C" & PL "C" & RL "B" & "N", "C" & NL "C" & DL 2 "C" & 2L Low "C" & LL

9 9 of 65 12/5/2014 1:13 PM Fig 5: Park/Neutral Switch Terminal ID OXYGEN SENSOR FEEDBACK VOLTAGE TEST 1. Warm engine to normal operating temperature. Connect analog voltmeter to terminals VF1 and E1 terminals of Data Link Connector No. 1 (DLC1). See Fig 6. Perform test procedures listed. See Fig 7 2. Depending on model application, some vehicles may be equipped with a main oxygen sensor, sub-oxygen sensor and a sensor heater. See OXYGEN SENSOR APPLICATION table. NOTE: Diagnostic trouble Codes 21, 25, 26, 27 and 28 (some models) are oxygen sensor circuit codes. For diagnostic trouble code charts, see articles listed below: 1. TESTS W/CODES - 4-CYL 2. TESTS W/CODES - V6

10 10 of 65 12/5/2014 1:13 PM OXYGEN SENSOR APPLICATION Application Type Main Oxygen Sensor Sub-Oxygen Sensor Sensor Heater Pickup X (1) X (2) X (1) (2) Applies to California models. Heater used on main oxygen sensor on all models. Heater used on sub-oxygen sensors on California models. Fig 6: Using Voltmeter For Testing Oxygen Sensor Feedback Voltage

11 11 of 65 12/5/2014 1:13 PM Fig 7: Performing Oxygen Sensor Feedback Voltage Test SUB-OXYGEN SENSOR NOTE: Sub-oxygen sensor may be used only on California applications on some models. See OXYGEN SENSOR APPLICATION table.

12 12 of 65 12/5/2014 1:13 PM 1. Warm engine to normal operating temperature. Check Engine Control Module (ECM) for stored diagnostic trouble code(s). See RETRIEVING TROUBLE CODES in articles listed below: 1. TESTS W/CODES - 4-CYL 2. TESTS W/CODES - V6 If sub-oxygen sensor or circuit fails, a diagnostic trouble Code 27 will set in Engine Control Module (ECM) memory. Clear diagnostic trouble code if present. See CLEARING TROUBLE CODES in articles listed below: 1. TESTS W/CODES - 4-CYL 2. TESTS W/CODES - V6 2. Drive vehicle at speeds less than 50 MPH for at least 5 minutes in 4th or 5th gear (M/T) or Drive (A/T). On all models, fully depress accelerator pedal for at least 2 seconds. 3. Stop engine and turn ignition off. Repeat steps and note if diagnostic trouble Code 27 exists again. If trouble Code 27 exists again, check sub-oxygen sensor circuit for continuity, shorts or grounds. Replace sub-oxygen sensor if circuit is okay. OXYGEN SENSOR HEATER NOTE: Oxygen sensor heater may be used only on California applications on some models. See OXYGEN SENSOR APPLICATION table. 1. Disconnect electrical connector from oxygen sensor. Using ohmmeter, measure resistance between oxygen sensor terminals +B and HT. See Fig Replace oxygen sensor if resistance is not within specification. See OXYGEN SENSOR HEATER RESISTANCE SPECIFICATIONS table. OXYGEN SENSOR HEATER RESISTANCE SPECIFICATIONS Application 68 F (20 C) Pickup

13 13 of 65 12/5/2014 1:13 PM Fig 8: Testing Oxygen Sensor Heater SUB-OXYGEN SENSOR HEATER NOTE: Sub-oxygen sensor heater may be used only on California applications on some models. See OXYGEN SENSOR APPLICATION table. Disconnect electrical connector from sub-oxygen sensor. Using ohmmeter, measure resistance between sensor terminals +B and HT. See Fig 9. Replace sub-oxygen sensor if resistance is not ohms at 68 F (20 C).

14 14 of 65 12/5/2014 1:13 PM Fig 9: Testing Sub-Oxygen Sensor Heater PICK-UP COILS See PICK-UP COIL AIR GAP and PICK-UP COIL RESISTANCE under IGNITION CHECKS in articles listed below: BASIC TESTING - 4-CYL BASIC TESTING - V6 THROTTLE POSITION SENSOR 1. Turn ignition off. Disconnect electrical connector from Throttle Position Sensor (TPS) on throttle body. Note terminal identification. See Fig 10 and Fig 11. NOTE: Some models require that vacuum be applied to throttle opener before checking

15 15 of 65 12/5/2014 1:13 PM TPS. See TPS RESISTANCE SPECIFICATIONS table. 2. Insert specified thickness feeler gauge between throttle stop screw and throttle lever and check resistance or continuity. See TPS RESISTANCE SPECIFICATIONS table. Replace or adjust TPS if not within specification. Fig 10: Checking Throttle Position Sensor (2.4L)

16 16 of 65 12/5/2014 1:13 PM Fig 11: Checking Throttle Position Sensor (3.0L) TPS RESISTANCE SPECIFICATIONS Application Type Clearance In. (mm) Terminals Tested Ohmmeter Reading 2.4L 0 (0) VTA & E ".022 (.56) IDL & E Or Less ".034 (.86) IDL & E2 No Continuity " Fully Open VTA & E ,100 " " VCC & E (1) 3.0L 0 (0) VTA & E ".020 (.51) IDL & E Or Less ".031 (.79) IDL & E2 No Continuity " Fully Open VTA & E ,100 " " VC & E (1) Apply vacuum to throttle opener before checking TPS. VEHICLE SPEED SENSOR 1. Vehicle speed sensor is located on transmission/transaxle and contains a 3-wire connector.

17 17 of 65 12/5/2014 1:13 PM Connect voltmeter and battery voltage to vehicle speed sensor terminals. See Fig While rotating vehicle speed sensor shaft, ensure voltage changes from zero to at least 11 volts. Voltage should change 4 times per revolution of the shaft. Replace vehicle speed sensor if voltage does not change as specified. Fig 12: Testing Vehicle Speed Sensor 4WD SWITCH 1. 4WD switch is located on passenger's side of transfer case. Remove switch from transfer case. Connect ohmmeter between switch terminals. 2. Push pin on end of switch inward and ensure continuity exists. No continuity should exist when switch pin is released (outward) position. Replace switch if defective. CONTROL UNITS FUEL PUMP ELECTRONIC CONTROL UNIT See FUEL DELIVERY under FUEL SYSTEM. RELAYS

18 18 of 65 12/5/2014 1:13 PM CIRCUIT OPENING RELAY 1. Ensure ignition is off. Remove circuit opening relay. See CIRCUIT OPENING RELAY LOCATION table. Using ohmmeter, check continuity between specified terminals. See Fig 13, Fig 14 and Fig Check circuit opening relay operation by applying battery voltage and ground and checking continuity between specified terminals. See Fig 13, Fig 14 and Fig 15. Replace circuit opening relay if defective. NOTE: Circuit opening relay may also be identified using appropriate illustration in THEORY/OPERATION article or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article. CIRCUIT OPENING RELAY LOCATION Application Pickup Location Behind Glove Box, Near Passenger's Side Kick Panel, Above ECM

19 19 of 65 12/5/2014 1:13 PM Fig 13: Testing Circuit Opening Relay (Step 1, Continuity)

20 20 of 65 12/5/2014 1:13 PM Fig 14: Testing Circuit Opening Relay (Step 2)

21 21 of 65 12/5/2014 1:13 PM Fig 15: Testing Circuit Opening Relay (Step 3, Operation) EFI MAIN RELAY 1. Ensure ignition is off. Remove EFI main relay. See EFI MAIN RELAY LOCATION table. Using ohmmeter, check continuity between specified terminals. See Fig Check EFI main relay operation by applying battery voltage and ground and checking continuity between specified terminals. See Fig Replace EFI main relay if defective. NOTE: The EFI main relay may also be identified using appropriate illustration in THEORY/OPERATION article or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article. EFI MAIN RELAY LOCATION

22 22 of 65 12/5/2014 1:13 PM Application Pickup Location Fuse/Relay Box Near Passenger's Side Front Corner Of Engine Bay Fig 16: Testing EFI Main Relay - Checking Continuity (2.4L)

23 23 of 65 12/5/2014 1:13 PM Fig 17: Testing EFI Main Relay - Checking Operation (2.4L)

24 24 of 65 12/5/2014 1:13 PM Fig 18: Testing EFI Main Relay - Checking Continuity (3.0L)

25 25 of 65 12/5/2014 1:13 PM Fig 19: Testing EFI Main Relay - Checking Operation (3.0L) IGNITION MAIN RELAY See IGNITION MAIN RELAY under IGNITION SYSTEM. FUEL SYSTEM FUEL DELIVERY NOTE: For fuel system pressure testing, see articles listed below: BASIC TESTING - 4-CYL BASIC TESTING - V6 Circuit Opening Relay See CIRCUIT OPENING RELAY under RELAYS. EFI Main Relay See EFI MAIN RELAY under RELAYS. Fuel Pump Relay

26 26 of 65 12/5/2014 1:13 PM See FUEL PUMP RELAY under RELAYS. FUEL CONTROL NOTE: Fuel injector solenoid resistor may also be referred to as MFI resistor, SFI resistor or solenoid resistor. Fuel Injectors 1. Ensure ignition is off. Disconnect electrical connector at fuel injector. Using ohmmeter, measure resistance between fuel injector electrical terminals. Replace fuel injector if resistance is not within specification. See FUEL INJECTOR RESISTANCE SPECIFICATIONS table. 2. To check fuel injector spray pattern and volume, remove fuel injector. See REMOVE/INSTALL /OVERHAUL article. Disconnect fuel hose from fuel filter outlet. Use Delivery Hose ( ) to install fuel injector between fuel filter and fuel pressure regulator. See Fig 20 and Fig Place fuel injector into a clean graduated container. Place vinyl tube on end of fuel injector to prevent fuel spillage. Install Jumper Wire (SST ) between +B and FP terminals of data link connector No. 1. Turn ignition on, with engine off to pressurize fuel system. NOTE: For proper location of data link connector No. 1 and terminal identification, see articles listed below: 1. BASIC TESTING - 4-CYL 2. BASIC TESTING - V6 Jumper wire is installed in data link connector No. 1 when checking fuel pump operation and fuel pressure. 4. Connect fuel injector tester to fuel injector for 15 seconds. Use Fuel Injector Tester ( ). 5. Measure fuel injector volume and check spray pattern. Test each fuel injector 2-3 times. Replace fuel injector if volume is not as specified. See FUEL INJECTOR VOLUME SPECIFICATIONS table. NOTE: Ensure difference between fuel injector volume on all fuel injectors is within specification. See FUEL INJECTOR VOLUME SPECIFICATIONS table. 6. Disconnect fuel injector tester. Ensure fuel leakage from end of fuel injector is one drop or less in specified time. See FUEL INJECTOR LEAKAGE SPECIFICATIONS table. Replace fuel injector if leakage exceeds specified amount. Turn ignition off and remove test equipment.

27 27 of 65 12/5/2014 1:13 PM FUEL INJECTOR RESISTANCE SPECIFICATIONS Application 68 F (20 C) Pickup FUEL INJECTOR VOLUME SPECIFICATIONS Application Cu. In. (cc) Pickup (45-55) Maximum Difference Between Each Fuel Injector.4 (6) FUEL INJECTOR LEAKAGE SPECIFICATIONS Application Pickup Leakage Time 1 Minute Fig 20: Testing Fuel Injector Spray Pattern & Volume (Step 1)

28 28 of 65 12/5/2014 1:13 PM Fig 21: Testing Fuel Injector Spray Pattern & Volume (Step 2) NOTE: Fuel pressure control system may also be referred to as fuel pressure-up system. Fuel Pressure Control System 1. Fuel pressure control system uses a fuel pressure control Vacuum Switching Valve (VSV). Fuel pressure control VSV is supplied voltage through EFI main relay. 2. Engine Control Module (ECM) will activate VSV by controlling ground circuit for approximately 90 seconds when restarting engine at normal operating temperature. Locate and remove fuel pressure control VSV. See FUEL PRESSURE CONTROL VSV LOCATION table.

29 29 of 65 12/5/2014 1:13 PM NOTE: Fuel pressure control VSV may also be identified using appropriate illustration in THEORY/OPERATION article or wire color. See appropriate wiring diagram in WIRING DIAGRAMS article. FUEL PRESSURE CONTROL VSV LOCATION Application Location 2.4L Near Center Of Valve Cover 3.0L Center VSV, Near Fuse/Relay Box At Passenger's Front Corner Of Engine Bay 3. Using ohmmeter, check resistance and for continuity between fuel pressure control VSV electrical terminals. Replace fuel pressure control VSV if no continuity exists or resistance is not within specification. See FUEL PRESSURE CONTROL VSV RESISTANCE SPECIFICATIONS table. 4. Ensure no continuity exists between each electrical terminal and fuel pressure control VSV body. Replace fuel pressure control VSV if continuity exists between electrical connector and fuel pressure control VSV body. 5. Check fuel pressure control VSV operation by applying air pressure to designated area and checking air passage, and then applying battery voltage and ground and retesting. See Fig 22 and Fig 23. Replace fuel pressure control VSV if defective. FUEL PRESSURE CONTROL VSV RESISTANCE SPECIFICATIONS Application Ohms Pickup 30-50

30 30 of 65 12/5/2014 1:13 PM Fig 22: Testing Fuel Pressure Control VSV (2.4L)

31 31 of 65 12/5/2014 1:13 PM Fig 23: Testing Fuel Pressure Control VSV (3.0L) Fuel Cut System 1. Install tachometer. Tachometer must be connected to proper terminals. See IDLE SPEED & MIXTURE in articles listed below: 1. ADJUSTMENTS - 4-CYL 2. ADJUSTMENTS - V6 CAUTION: Some tachometers may not be compatible with ignition system. Consult tachometer manufacturer before connecting tachometer to system. To avoid possible damage to ignitor and/or coil, DO NOT allow tachometer terminal to become grounded. 2. Start engine and warm to normal operating temperature. Ensure all accessories are off. Gradually increase engine RPM to maintain at least specified engine speed. See FUEL CUT SYSTEM TESTING SPECIFICATION table. FUEL CUT SYSTEM TESTING SPECIFICATION

32 32 of 65 12/5/2014 1:13 PM Application Engine RPM Pickup Using stethoscope, check for fuel injector operating sound. Ensure when throttle lever is released, fuel injector stops operating momentarily (fuel cut RPM) and then resumes operating (fuel return RPM). 4. Ensure fuel cut RPM (if available) and fuel return RPM are within specification. See FUEL CUT SYSTEM SPECIFICATIONS table. Shut engine off. Disconnect tachometer. FUEL CUT SYSTEM SPECIFICATIONS (1) Application Fuel Cut RPM Fuel Return RPM 2.4L 2WD M/T (3) Except 2WD M/T L A/T (2) 1500 M/T (2) 1300 (1) (2) (3) Check with A/C off. Fuel cut specification is not available from manufacturer. Check with brake pedal depressed and brakelights on. Cold Start Injector 1. Disconnect negative battery cable. Disconnect cold start injector wiring harness connector. 2. Using ohmmeter, measure resistance between electrical terminals of cold start injector. Replace cold start injector if resistance is not 2-4 ohms. Remove cold start injector. See information in REMOVE/INSTALL/OVERHAUL article in the ENGINE PERFORMANCE section. 3. On 2.4L, install Union Adapters (SST ) with NEW gaskets on cold start injector and delivery pipe. Connect delivery hose to union adapters. See Fig 24 and Fig On 3.0L, install cold start injector or delivery hose with union bolt and NEW gaskets on cold start injector. 5. Reconnect negative battery cable. Connect Jumper Wire (SST ) between terminals FP and +B of data link connector No. 1. Turn ignition on, with engine off to pressurize fuel system. NOTE: For proper location of data link connector No. 1 and terminal identification, see articles listed below:

33 33 of 65 12/5/2014 1:13 PM BASIC TESTING - 4-CYL 2. BASIC TESTING - V6 Jumper wire is installed in data link connector No. 1 when checking fuel pump operation and fuel pressure. Place tip of cold start injector in a container. Connect cold start injector tester to cold start injector. Use Cold Start Injector Tester (SST ). CAUTION: Perform cold start injector test in shortest possible time to check fuel spray pattern. 7. Connect cold start injector tester to battery. See Fig 24 and Fig 25. Ensure fuel spray pattern is an even cone shape. Disconnect cold start injector tester from battery. 8. Check for fuel leakage from cold start injector. Maximum leakage should be one drop per minute with fuel pressure applied. Replace cold start injector if defective. Disconnect negative battery cable and test equipment. NOTE: Cold start injector is controlled by cold start injector time switch when ignition is turned on. Cold Start Injector Time Switch For test procedures, see COLD START INJECTOR TIME SWITCH under ENGINE SENSORS & SWITCHES.

34 34 of 65 12/5/2014 1:13 PM Fig 24: Testing Cold Start Injector (Step 1)

35 35 of 65 12/5/2014 1:13 PM Fig 25: Testing Cold Start Injector (Step 2) IDLE CONTROL SYSTEM AUXILIARY AIR VALVE SYSTEM NOTE: Install tachometer when checking auxiliary air valve system. Ensure tachometer is connected to proper terminals. See IDLE SPEED & MIXTURE in articles listed below for tachometer connections: ADJUSTMENTS - 4-CYL ADJUSTMENTS - V6 CAUTION: Some tachometers may not be compatible with ignition system. Consult

36 36 of 65 12/5/2014 1:13 PM tachometer manufacturer before connecting tachometer to system. To avoid possible damage to ignitor and/or coil, DO NOT allow tachometer terminal to become grounded. 1. Install tachometer. With engine coolant temperature less than 176 F (80 C), start engine. 2. With engine idling, turn idle speed adjusting screw inward to bottom of bore while counting number of revolutions. See Fig 26 and Fig 27. Engine speed should decrease noticeably. 3. Return idle speed adjusting screw to original position. Warm engine to normal operating temperature. Repeat step 2). Engine speed should not change or should drop slightly. 4. If engine RPM does not respond as indicated, check for vacuum leaks or restricted auxiliary air valve circuit. If no defects are found, replace auxiliary air valve, located on bottom of valve body.

37 37 of 65 12/5/2014 1:13 PM Fig 26: Idle Speed Adjusting Screw ID (2.4L)

38 38 of 65 12/5/2014 1:13 PM Fig 27: Idle Speed Adjusting Screw ID (3.0L) A/C IDLE-UP VALVE Testing information not available from manufacturer. IGNITION SYSTEM NOTE: For basic ignition checks, see articles listed below: BASIC TESTING - 4-CYL BASIC TESTING - V6 TIMING CONTROL SYSTEMS Knock Sensor See KNOCK SENSOR under ENGINE SENSORS & SWITCHES. EMISSION SYSTEMS & SUB-SYSTEMS

39 39 of 65 12/5/2014 1:13 PM EXHAUST GAS RECIRCULATION (EGR) SYSTEM TEST NOTE: EGR systems contain different components and have different operating parameters depending on application. See Fig When testing EGR system and components, use proper illustration to determine component location. 1. Ensure EGR vacuum modulator filter(s) are clean and in good condition. Clean filter(s) with compressed air (if necessary). 2. Using "T" connector, install vacuum gauge in vacuum line to EGR valve. Start engine. Ensure engine runs idles smoothly to ensure proper seating of EGR valve. NOTE: The EGR system components can be checked with engine coolant temperature less than minimum temperature and engine at specified engine RPM. Fig 28: Identifying Ports & Testing EGR Vacuum Modulator 3. Operate engine with engine coolant temperature less than minimum temperature and at

40 40 of 65 12/5/2014 1:13 PM specified RPM. See EGR TESTING SPECIFICATIONS table. No vacuum reading should be obtained. 4. Warm engine to normal operating temperature. Operate engine at specified engine RPM again. See EGR TESTING SPECIFICATIONS table. Ensure a low vacuum reading is now obtained. 5. Disconnect vacuum hose from port "R" of EGR vacuum modulator. See Fig Using additional hose, connect port "R" of EGR vacuum modulator directly to intake manifold. High vacuum reading should be obtained at specified engine RPM. See EGR TESTING SPECIFICATIONS table. NOTE: Engine should misfire due to large amounts of exhaust gas being injected into intake manifold. 7. Remove vacuum hose and reconnect original vacuum hose to EGR vacuum modulator. 8. To check EGR valve operation, remove vacuum hose from EGR valve. Using vacuum pump, apply vacuum directly to EGR valve with engine idling. Engine should run rough or stall. If EGR system does not operate as described, each individual component should be tested. EGR TESTING SPECIFICATIONS Application Minimum Temperature Engine RPM 2.4L Calif. Models 93 F (34 C) (1) 3500 All Others 86 F (30 C) (1) L 118 F (48 C) 3500 (1) Check at 3000 RPM when applying vacuum to EGR valve. EGR VACUUM MODULATOR 1. Mark locations and disconnect vacuum hoses from EGR vacuum modulator. Block ports "P" and "R" of EGR vacuum modulator. See Fig 28. NOTE: Ports "P" and "R" are the double ports on side of EGR vacuum modulator. Port "Q" is the single port on side of EGR vacuum modulator. 2. Apply air pressure to port "Q". See Fig 28. Air should pass freely through air filter side of EGR vacuum modulator. 3. Start and operate engine at specified RPM. See EGR VACUUM MODULATOR TESTING SPECIFICATIONS table. Repeat test procedures in steps 1) and 2). Strong resistance of

41 41 of 65 12/5/2014 1:13 PM airflow should be felt. Replace EGR vacuum modulator if resistance is not felt. Reconnect vacuum hoses to proper locations. EGR VACUUM MODULATOR TESTING SPECIFICATIONS Application Engine RPM Pickup 3500 EGR THERMAL VACUUM VALVE (TVV) 2.4L (Except CA) 1. Drain cooling system and remove TVV. See Fig Use cool water to cool threaded end of TVV to minimum temperature according to application. See TVV TESTING SPECIFICATIONS table. 2. Apply air pressure to the lower port. Air should pass through air filter located on top of TVV. Using hot water, heat threaded end of TVV until temperature exceeds maximum temperature according to application. See TVV TESTING SPECIFICATIONS table. 3. Apply air pressure to the lower port. Air should pass through upper port but not through the air filter. Replace TVV if defective. Reinstall and fill cooling system. TVV TESTING SPECIFICATIONS Application Type Minimum Temperature Maximum Temperature Pickup 86 F (30 C) 111 F (44 C) EGR VACUUM SWITCHING VALVE (VSV) NOTE: When testing EGR VSV, use proper illustration to determine component location. See Fig The EGR VSV may be referred to as the VSV. 3.0L 2.4L (CA) 1. Disconnect electrical connector from EGR VSV. Using ohmmeter, check resistance between EGR VSV electrical terminals. 2. Replace EGR VSV if resistance is not within specification. See EGR VSV RESISTANCE SPECIFICATIONS table. Ensure no continuity exists between each electrical terminal and EGR VSV body. Replace EGR VSV if continuity exists between any electrical terminal and VSV body. 3. Apply air pressure to port "E" (without battery connected). See Fig 29 and Fig 30. Air pressure should flow from port "G". Connect battery voltage and ground to EGR VSV electrical terminals. See Fig 29 and Fig 30. Apply air pressure to port "E". Air pressure should flow through the air filter. Replace EGR VSV if defective.

42 42 of 65 12/5/2014 1:13 PM 1. Disconnect electrical connector from EGR VSV. Using ohmmeter, check resistance between EGR VSV electrical terminals. 2. Replace EGR VSV if resistance is not within specification. See EGR VSV RESISTANCE SPECIFICATIONS table. Check that no continuity exists between each electrical terminal and EGR VSV body. Replace EGR VSV if continuity exists between any electrical terminal and VSV body. 3. Apply air pressure to port "E" (without battery connected). See Fig 29 and Fig 30. Air pressure should not flow through port "F". Connect battery voltage and ground to EGR VSV electrical terminals. See Fig 29 and Fig 30. Apply air pressure to port "E". Air pressure should flow from port "F". Replace EGR VSV if defective. EGR VSV RESISTANCE SPECIFICATIONS Application Ohms 2.4L (Calif.) L 30-50

43 43 of 65 12/5/2014 1:13 PM Fig 29: Testing EGR VSV Operation (3.0L)

44 44 of 65 12/5/2014 1:13 PM Fig 30: Testing EGR VSV Operation (2.4L CA)

45 45 of 65 12/5/2014 1:13 PM Fig 31: EGR System Diagram (2.4L Except CA) Fig 32: EGR System Components (2.4L Except CA)

46 46 of 65 12/5/2014 1:13 PM Fig 33: EGR System Operating Parameters (2.4L Except CA) Fig 34: EGR System Diagram (2.4L CA)

47 47 of 65 12/5/2014 1:13 PM Fig 35: EGR System Components (2.4L CA)

48 48 of 65 12/5/2014 1:13 PM Fig 36: EGR System Operating Parameters (2.4L CA) Fig 37: EGR System Diagram (3.0L)

49 49 of 65 12/5/2014 1:13 PM Fig 38: EGR System Components (3.0L)

50 50 of 65 12/5/2014 1:13 PM Fig 39: EGR System Operating Parameters (3.0L) Fig 40: Fuel Evaporation System Components (3.0L)

51 51 of 65 12/5/2014 1:13 PM Fig 41: Fuel Evaporation Operating Parameters (3.0L) Fig 42: Fuel Evaporation System Components (2.4L)

52 52 of 65 12/5/2014 1:13 PM Fig 43: Fuel Evaporation Operating Parameters (2.4L) NOTE: The EVAP Thermal Vacuum Valve (TVV) may be referred to as EVAP Thermal Valve (TV). EVAP Thermal Vacuum Valve (3.0L) 1. Drain cooling system. Remove TVV, located in coolant passage and contains 2 vacuum hoses which go to the charcoal canister and throttle body. 2. Use cool water to cool threaded end of TVV to less than 95 F (35 C). Apply air pressure to top port on TVV. Ensure TVV is closed and no air will pass through lower port. 3. Heat water to greater than 129 F (54 C). Apply air pressure to top port on TVV. Ensure TVV is open and air passes through lower port. Replace TVV if defective. Apply thread sealant to threads of TVV and reinstall. Fill cooling system. Charcoal Canister 1. Disconnect hoses from charcoal canister. Check for clogged filter and/or stuck check valve by applying low air pressure to port "A". See Fig 44. Ensure air flows freely from other ports on charcoal canister. 2. Apply low air pressure to port "B". See Fig 44. Ensure no air flows from any other ports on charcoal canister. Replace charcoal canister if defective. 3. To clean charcoal canister filter, apply 43 psi (3 kg/cm 2 ) air pressure to port "A" while holding port "B" closed. Ensure no activated carbon comes out of charcoal canister. DO NOT attempt to wash out charcoal canister.

53 53 of 65 12/5/2014 1:13 PM Fig 44: Identifying Charcoal Canister Ports POSITIVE CRANKCASE VENTILATION (PCV) 1. Remove PCV valve. Attach hose to PCV valve. Blow air from cylinder head side of PCV valve. Ensure air passes easily through PCV valve. 2. Blow air from intake manifold side of PCV valve. Ensure air passes through PCV valve with some restriction. Replace PCV valve if valve does not function as described. PULSED SECONDARY AIR INJECTION SYSTEM NOTE: Pulsed Secondary Air Injection (PAIR) system may be referred to as the Air Suction (AS) system. PAIR system has different operating parameters depending on application. See Fig

54 54 of 65 12/5/2014 1:13 PM Fig 45: PAIR System Diagram (2.4L)

55 55 of 65 12/5/2014 1:13 PM Fig 46: PAIR System Components (2.4L) Fig 47: PAIR System Operating Parameters (2.4L)

56 56 of 65 12/5/2014 1:13 PM Fig 48: PAIR System Diagram (3.0L)

57 57 of 65 12/5/2014 1:13 PM Fig 49: PAIR System Components (3.0L) Fig 50: PAIR System Operating Parameters (3.0L) PAIR System Test (2.4L) 1. Check hoses and tubes for cracks, kinks, damage or loose connections. Ensure engine

58 58 of 65 12/5/2014 1:13 PM coolant temperature is less than 86 F (30 C). Disconnect No. 1 air hose from air cleaner case. See Fig Start engine and allow to idle. Ensure bubbling sound is heard from No. 1 air hose. 3. Warm engine until engine coolant temperature is greater than 104 F (40 C). Ensure bubbling sound is not heard from No. 1 air hose with engine idling. 4. Increase engine speed and quickly close the throttle. Ensure bubbling noise at No. 1 air hose momentarily stops. If system does not operate correctly, check individual components. PAIR System Test (3.0L) 1. Check hoses and tubes for cracks, kinks, damage or loose connections. Ensure engine coolant temperature is less than 77 F (25 C). Disconnect No. 1 air hose from air pipe, above air intake. See Fig Start engine and allow to idle. Ensure bubbling sound is heard from air pipe. Warm engine until engine coolant temperature is greater than 95 F (35 C). Ensure bubbling sound is not heard from air pipe with engine idling. 3. Increase engine speed to 2000 RPM and quickly close throttle. Ensure bubbling noise at air pipe momentarily stops. If system does not operate correctly, check individual components. PAIR Check Valve 1. Remove PAIR check valve. See Fig Apply air pressure to Orange side of PAIR check valve. Air should pass through PAIR check valve. 2. Apply air pressure to Black side of PAIR check valve. Air should not pass through PAIR check valve. Replace PAIR check valve if defective. PAIR Reed Valve 1. Remove PAIR reed valve. Using vacuum pump, apply vacuum to PAIR reed valve vacuum diaphragm. Apply air pressure to PAIR reed valve. See Fig 51 and Fig 52. Ensure valve is open and air passes through PAIR reed valve. 2. Release vacuum from PAIR reed valve vacuum diaphragm. Apply air pressure to PAIR reed valve. See Fig 51 and Fig 52. Ensure valve is closed and no air passes through PAIR reed valve. Replace PAIR reed valve if defective.

59 59 of 65 12/5/2014 1:13 PM Fig 51: Checking PAIR Reed Valve (2.4L)

60 60 of 65 12/5/2014 1:13 PM Fig 52: Checking PAIR Reed Valve (3.0L) PAIR Vacuum Switching Valve 1. Disconnect electrical connector from PAIR VSV. See Fig Using ohmmeter, ensure resistance between electrical terminals of VSV is within F (20 C). 2. Ensure no continuity exists between each electrical terminal and body of VSV. Apply air pressure to port "E". Ensure air passes out air filter. Perform STEP 1. See Fig Connect battery voltage and ground to VSV terminals. Apply air pressure to port "E". Ensure air passes out port "F". Perform STEP 2. See Fig 53. Replace VSV if defective.

61 61 of 65 12/5/2014 1:13 PM Fig 53: Checking PAIR VSV THROTTLE CONTROLS NOTE: When testing throttle control systems, tachometer may be required. Ensure tachometer is connected to proper terminals. For tachometer connections, see IDLE SPEED & MIXTURE in articles listed below: ADJUSTMENTS - 4-CYL ADJUSTMENTS - V6 DASHPOT CONTROL SYSTEM 2.4L M/T & 3.0L 1. Warm engine to normal operating temperature. Ensure idle speed is correct. See IDLE SPEED & MIXTURE in articles listed below: 1. ADJUSTMENTS - 4-CYL 2. ADJUSTMENTS - V6

62 62 of 65 12/5/2014 1:13 PM 2. Start engine. Maintain engine speed at specified testing RPM. See DASHPOT TESTING SPECIFICATIONS table. Plug Vacuum Transmitting Valve (VTV) hole with your finger. See Fig Release throttle. Dashpot should be extended and dashpot setting RPM should be as specified. See DASHPOT TESTING SPECIFICATIONS table. If dashpot setting RPM is incorrect, rotate dashpot adjusting screw to obtain correct RPM. See Fig Repeat step 3) and ensure proper adjustment is obtained. To check Vacuum Transmitting Valve (VTV) operation, operate engine at dashpot testing RPM for a few seconds. Release throttle. Ensure engine returns to idle in approximately one second. 5. Install separator, filter and cap. Install filter with the coarse surface facing outward (away from dashpot). Remove cap, filter and separator from dashpot. See Fig 54. DASHPOT TESTING SPECIFICATIONS Application Testing RPM (1) Dashpot Setting RPM 2.4L With M/T L (1) With electric cooling fan off (if equipped). Fig 54: Identifying Dashpot & Components

63 63 of 65 12/5/2014 1:13 PM Fig 55: Identifying Typical Vacuum Transmitting Valve Fig 56: Adjusting Typical Dashpot THROTTLE OPENER

64 64 of 65 12/5/2014 1:13 PM 2.4L With A/T 1. Warm engine to normal operating temperature. Ensure idle speed is correct. See IDLE SPEED & MIXTURE in articles listed below: 1. ADJUSTMENTS - 4-CYL 2. ADJUSTMENTS - V6 2. Disconnect and plug vacuum hose at throttle opener, located on side of throttle body. Start engine. Maintain engine speed at 2500 RPM. Release throttle and note engine speed. Engine speed should be within specification. See THROTTLE OPENER SPECIFICATIONS table. 3. If engine speed is not within specification, rotate throttle opener adjusting screw until correct engine speed is obtained. See Fig 57. Reinstall vacuum hose on throttle opener. Fig 57: Adjusting Throttle Opener (Similar) 3.0L 1. Warm engine to normal operating temperature. Ensure idle speed is correct. See IDLE SPEED & MIXTURE in articles listed below: 1. ADJUSTMENTS - 4-CYL 2. ADJUSTMENTS - V6

65 65 of 65 12/5/2014 1:13 PM 2. Disconnect and plug vacuum hose at throttle opener, located on side of throttle body. Start engine. Maintain engine speed at 2500 RPM. Release throttle and note engine speed. Engine speed should be within specification. See THROTTLE OPENER SPECIFICATIONS table. 3. Replace throttle body if engine speed is not within specification. Reinstall vacuum hose on throttle opener. Start engine and ensure engine returns to correct idle speed. THROTTLE OPENER SPECIFICATIONS Application (1) RPM 2.4L With A/T 2WD WD L (1) With electric cooling fan turned off (if equipped).