Table of Contents ELECTRONIC FUEL INJECTION Section 3B - Troubleshooting and Diagnostics TROUBLESHOOTING AND DIAGNOSTICS Specifications........................... 3B-1 Special Tools........................... 3B-2 Control and Function.................... 3B-3 EFI System Diagnostic Procedures........ 3B-3 Pressure Regulator Test............... 3B-3 Mechanical Fuel Pump Test............ 3B-4 Injector Operation Test................ 3B-5 Fail Safe Function Table.................. 3B-6 Self-Diagnosis.......................... 3B-7 Diagnosis Code Information........... 3B-7 Diagnosis of Electronic Control System.. 3B-7 Diagnostic Code Chart................ 3B-10 3 B Specifications FUEL SYSTEM FUEL INJECTION Fuel Pump Type Fuel Pump: Discharge (@ 3000 rpm) Pressure (Maximum) Plunger Stroke Fuel Tank Capacity Fuel Injection System Idle rpm (In Neutral) Warm Idle rpm (In Forward Gear) Warm Fuel Pressure @ 1500rpm External (Plunger/Diaphragm) 65 L/h (17 gph) 49 kpa (7 psi) 5.85-9.05 mm (0.23-0.36 in.) Accessory Batch (1 & 4) - (2 & 3) 750 ± 50 rpm 700 ± 50 rpm 283-304 kpa (41-44 psi) 90-881980R02 APRIL 2003 Page 3B-1
TROUBLESHOOTING AND DIAGNOSTICS Special Tools 1. Fuel Pressure Gauge 91-16850A7 or Fuel Pressure Gauge 91-852087A3. 91-16850A7 2. Mityvac vacuum gauge (obtain locally). 91-852087A3 3. Malfunction Indicator Lamp 99056A1 or Diagnostic Lamp 91-8847931A1 99056A1 91-884793A1 58680 59129 Page 3B-2 90-881980R02 APRIL 2003
Control and Function TROUBLESHOOTING AND DIAGNOSTICS Ignition Timing Fuel Injection Timing Air/Fuel Control Function Crank Position Sensor Detects the crankshaft position and engine speed Throttle Position Sensor Detects the open degree of the throttle valve Water Temperature Sensor Detects engine temperature Manifold Absolute Pressure (MAP) Sensor Intake Air Temperature Sensor Detects intake air pressure of the intake manifold Detects intake air temperature Shift Position Switch Determines the shift position. (Neutral: ON, Forward or Reverse: OFF) Oil Pressure Switch Detects Oil Pressure EFI System Diagnostic Procedures Pressure Regulator Test 1. Install the fuel pressure gauge onto the pressure check valve (located on top of the fuel rail). 2. Start the engine. Fuel pressure should be within specification. a b c 91-16850A7 a - Fuel pressure gauge b - Pressure check valve c - Pressure regulator 90-881980R02 APRIL 2003 Page 3B-3
TROUBLESHOOTING AND DIAGNOSTICS Mechanical Fuel Pump Test NOTE: Do not over-pressurize the fuel pump. Excessive pressure may cause air to leak out. 1. Install the Mityvac onto the fuel pump as shown. 2. Test 1: Pressurize the fuel pump to 50 kpa (7psi). Fuel pump should hold this amount of pressure. Perform this test on input and output side of fuel pump. 3. Test 2: Apply 14 kpa (4 in. Hg) vacuum to fuel pump. Fuel pump should hold this amount of vacuum. a Test 1 b Test 1 Test 2 a - Fuel pump b - Mityvac Page 3B-4 90-881980R02 APRIL 2003
Injector Operation Test TROUBLESHOOTING AND DIAGNOSTICS 1. Start the engine. Fully close the throttle valves. 2. Hold the screwdriver so it is making contact with the fuel injector body. The fuel injector should have a solenoid valve operating sound. Verify this on all injectors. IMPORTANT: If no sound is coming from the injector then no fuel is being sprayed. Verify the high pressure fuel pump is operating properly. a b a - Screwdriver b - Fuel injector (4) NOTE: Refer to Section 2A for testing of the Throttle Position Sensor and Engine Temperature Sensor. 90-881980R02 APRIL 2003 Page 3B-5
TROUBLESHOOTING AND DIAGNOSTICS Fail Safe Function Table Symptoms Abnormal signal from crank position sensor Abnormal signal from throttle position sensor Abnormal signal from Manifold Absolute Pressure (MAP) sensor Abnormal signal from water temperature sensor Abnormal signal from intake air temperature sensor Abnormal signal from engine stop switch FAIL SAFE FUNCTION Ignition Fuel Injection IAC Engine Conditions Four cylinder ignition is fixed at 4 ATDC When throttle opening angle is less than -10 or more than 100 : Ignition is fixed at 10 BTDC When the intake air pressure is less than 13 kpa (1.9 psi) or more than 100 kpa (17.4 psi): Ignition is fixed at 10 BTDC When less than 0.1 V or more than 4.52 V are detected (substitutes the intake air temperature sensor): Ignition is fixed at 10 BTDC When less than 0.1 V or more than 4.52 V are detected (the intake air temperature sensor is fixed at 4 : Ignition is fixed at 10 BTDC On is detected Ignition is cut Cylinders with no input signal will be stopped When the throttle opening angle is less than -10 or more than 100 : Injection is controlled only by the boost map When the intake air pressure is less than 13 kpa (1.9 psi) or more than 100 kpa (17.4 psi): Injection is controlled with throttle opening map When less than 0.1 V or more than 4.52 V are detected (substitutes the intake air temperature sensor): Normal Operation When less than 0.1 V or more than 4.52 V are detected (the intake air temperature sensor is fixed at 4 : Normal Operation On is detected Ignition is cut 900 rpm 900 rpm 900 rpm 900 rpm 900 rpm IAC is stopped Engine idling speed increases. Top speeds cannot be reached. Engine idling speed increases. Top speeds cannot be reached. Engine idling speed increases. Top speeds can be reached. Engine idling speed increases. Top speeds can be reached. Engine idling speed increases. Top speed can be reached. Engine is stopped. Shift switch open 900 rpm Engine idling speed increases. Top speeds can be reached. Page 3B-6 90-881980R02 APRIL 2003
Self-Diagnosis TROUBLESHOOTING AND DIAGNOSTICS Diagnosis Code Information 1. Normal condition (no defective part or irregular processing is found). Single flash is given every 5 seconds. a. Light on, 0.33 second b. Light off, 5 seconds 2. Trouble code indication. Example: The illustration indicates code number 23. a. Light on, 0.33 second b. Light off, 0.33 second c. Light off, 1.65 seconds d. Light off, 5 seconds. Diagnosis of the Electronic Control System 1. Remove wire connector test plug cap. 90-881980R02 APRIL 2003 Page 3B-7
TROUBLESHOOTING AND DIAGNOSTICS 2. Install Malfunction Indicator Lamp a. Model Year 2001 and Prior Install Malfunction Indicator Lamp (MIL) p/n 99056A1, or create your own test light. (1.) Remove rubber plugs from engine harness bullet connectors. (2.) Connect leads of the Malfunction Indicator Lamp (MIL) p/n 99056A1 to the engine harness connectors. RED/BLACK 99056A1 BLUE/WHITE NOTE: When performing this diagnosis, all of the electrical wires must be properly connected. BLUE/WHITE RED/BLACK Page 3B-8 90-881980R02 APRIL 2003
b. Model Year 2002 and Newer Install Malfunction Indicator Lamp (MIL) p/n 91-884793A1. TROUBLESHOOTING AND DIAGNOSTICS NOTE: This new service tool must be used on 2002 model year product. The new tool consists of the previous diagnostic lamp 99056A1 and an additional harness with a 3 pin terminal connector. (1.) Remove rubber plug from engine harness bullet connector. (2.) Connect the harness terminal to the diagnostic test terminal. (3.) Connect the lamp wire bullet terminal to the BLUE/WHITE wire bullet terminal on the engine harness. a b c d a - Lamp wire b - Lamp wire c - GREEN/RED wire (not used) d - Harness terminal 59129 a b a - Harness terminal b - Bullet terminal 59130 90-881980R02 APRIL 2003 Page 3B-9
TROUBLESHOOTING AND DIAGNOSTICS 3. Check diagnosis codes (reference chart) a. Code 1 is indicated - normal b. Code 13-29 indicated - Check the applicable parts. c. Code 33-44 indicated - Microcomputer processing information. CHECKING STEPS 1. Start the engine and let it idle. 2. Check the malfunction indicator lamp s flash pattern to determine if there are any malfunctions. Diagnostic Code Chart NOTE: The ignition key must be returned to the OFF position for 5 seconds to clear a corrected failure code. NOTE: When more than one problem is detected, the malfunction indicator lamp light flashes in the pattern of the lowest numbered problem. After that problem is corrected and the failure code is cleared, the lamp flashes in the pattern of the next lowest numbered problem. This continues until all of the problems are detected and corrected. Code Symptoms 13 Incorrect crank position sensor input signal 15 Incorrect engine cooling water temperature sensor input signal 18 Incorrect throttle position sensor input signal 19 Incorrect battery positive voltage 23 Incorrect intake air temperature sensor input signal 28 Incorrect shift position switch 29 Incorrect manifold air pressure sensor input signal (out of normal operating range) (33) Ignition timing is being slightly corrected (when starting a cold engine) (37) Intake passage air leakage (44) Engine stop switch control operating Page 3B-10 90-881980R02 APRIL 2003
DIAGNOSIS/CORRECTION COMPLETED 1. Remove Malfunction Indicator Lamp (MIL). 2. Reinstall rubber plugs in engine harness bullet connectors. 3. Reinstall connector test plug cap. TROUBLESHOOTING AND DIAGNOSTICS a a - Plug cap 90-881980R02 APRIL 2003 Page 3B-11