Engine Controls - Basic Diagnostic Procedures: Other Isuzu Rodeo II

Compression

Check engine mechanical condition with a compression gauge, vacuum gauge, or an engine analyzer. If compression gauge is used, see COMPRESSION SPECIFICATIONS table. Ensure engine cranking speed is about 300 RPM. If vacuum gauge is used, check for low or unstable vacuum condition. If engine analyzer is used, see manufacturer's manual for specific instructions.

COMPRESSION SPECIFICATIONS

Exhaust System Backpressure

The exhaust system can be checked with a vacuum or pressure gauge. If using a pressure gauge, remove oxygen sensor or air injection check valve (if equipped). Connect a 0-5 psi pressure gauge and run engine at 2000 RPM. If exhaust system backpressure is greater than 2 psi, exhaust system or catalytic converter is plugged.

If a vacuum gauge is used, connect vacuum gauge hose to intake manifold vacuum port and start engine. Open throttle part way and hold. Observe vacuum gauge. If vacuum gauge reading slowly drops after stabilizing, check exhaust system for restriction.

Passport 2.2L, Rodeo & Rodeo Sport 2.2L

1. Perform On-Board Diagnostic II (OBD-II) System Check. See SELF-DIAGNOSTICS - 2.2L article. After performing OBD-II system check, go to next step.
2. Install Tech II scan tool. Following manufacturer's instructions, check for stored DTCs. If no DTCs are stored, go to next step. If any DTCs are stored, diagnose DTC. See appropriate diagnostic test procedure in SELF-DIAGNOSTICS - 2.2L article.
3. Check IG. COIL fuse (15-amp) and ENG. fuse (15-amp) located in dashboard fuse block. Check ECM fuse (15-amp) located in underhood fuse/relay block. If any fuse is blown, go to next step. If fuses are okay, go to step 5 .
4. Check for short to ground in appropriate circuits. See WIRING DIAGRAMS article. Repair as necessary. Replace any blown fuses.
5. Turn ignition on. With a test light connected to ground, probe IG. COIL fuse (15-amp) and ENG. fuse (15-amp) located in underdash fuse block and ECM fuse (15-amp) located in underhood fuse/relay block. If test light illuminates at all fuses, go to step 7 . If test light does not illuminate at all fuses, go to next step.
6. Repair open in appropriate ignition feed circuit. See WIRING DIAGRAMS article. Retest system.
7. Turn ignition off. Disconnect ignition secondary wire at coil No. 1. Install spark tester at end of secondary wire. While cranking engine, check for crisp, Blue spark. If poor or no spark is found, go to next step. If spark is okay, go to step 16 .
8. Disconnect Ignition Control Module (ICM) harness connector. Check for open or short circuit in wires between ICM and PCM. See WIRING DIAGRAMS article. If wires are okay, go to step 10 . If any problems were found in either wire, go to next step.
9. Repair open or short circuit in wires between ICM and PCM as necessary. Retest system.
10. Turn ignition on. Using DVOM, measure voltage at Black/Orange wire of ICM harness connector. If battery voltage is present, go to step 12 . If battery voltage is not present, go to next step.
11. Repair open circuit in Black/Orange wire between IG COIL fuse (15-amp) and ICM. Retest system.
12. Turn ignition switch off. Check for open in ICM ground circuit (Black/Red wire). If problem is found, go to next step. If problem is not found, go to step 14 .
13. Locate and repair open circuit in ICM ground (Black/Red wire). Retest system.
14. Replace ICM. Attempt to start engine. If engine does not start, go to next step.
15. Replace and reprogram PCM. See PROGRAMMING in SELF-DIAGNOSTICS - 2.2L. Retest system.
16. Turn ignition off. Using DVOM, measure ignition coil primary resistance. If primary resistance is .8-18 ohms, go to next step. If resistance is not as specified, go to step 18 .
17. Measure ignition coil secondary resistance. If secondary resistance is 9000-12,000 ohms, go to step 19 . If secondary resistance is not as specified, go to next step.
18. Replace ignition coil. Retest system.
19. Measure resistance of each coil-to-spark plug secondary ignition wire. If resistance is greater than 10 k/ohms per foot, go to next step. If resistance is not greater than specification, go to step 21 .
20. Replace any spark plug wires with resistance greater than 10 k/ohms per foot. Verify engine operation. If no faulty spark plug wires were found, go to next step.
21. Remove all spark plugs. Inspect spark plugs for fouling, loose or missing electrodes, or cracked insulators. Clean or replace spark plugs as necessary and go to next step. If spark plugs are okay, go to step 33 .
22. Attempt to start engine. If problem is still present, go to next step.
23. Turn ignition off. Install fuel pressure gauge to fuel supply line test fitting. Turn ignition on. If fuel pressure is 43-55 psi (3.0-3.9 kg/cm 2 ) and holds steady for 2 seconds, go to step 24 . If fuel pressure is not 43-55 psi (3.0-3.9 kg/cm 2 ) or does not hold steady for 2 seconds, go to next step.
24. If fuel pressure is not present, go to «FUEL SYSTEM DIAGNOSIS»(ref-12119-S37790422272000121100000) under FUEL SYSTEM. If any fuel pressure is present, go to «FUEL SYSTEM ELECTRICAL TEST»(ref-12119-S09204602672000121100000) under FUEL SYSTEM.
25. Install Injector Tester (J-39021) and switch box at injector test connector, and activate fuel injector. If fuel pressure drops, go to next step. If fuel pressure does not drop, go to «FUEL SYSTEM DIAGNOSIS»(ref-12119-S37790422272000121100000) under FUEL SYSTEM.
26. Pressurize system by turning ignition on. Using injector switch box, test each injector for pressure drop. If a pressure drop is present at each injector, go to next step. If a pressure drop is not present at each injector, go to «FUEL SYSTEM DIAGNOSIS»(ref-12119-S37790422272000121100000) under FUEL SYSTEM.
27. Remove Injector Tester (J-39021) and switch box. Connect Injector Test Light (J-39021-45) to injector test harness connector. Crank engine. If any tester lights blink while engine is cranking, go to step 33 . If no tester lights blink while engine is cranking, go to next step.
28. Raise and support vehicle. Disconnect Crankshaft Position (CKP) sensor connector. Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at CKP sensor harness terminal No. 2 (Green wire). If test light does not illuminate, repair open Green wire. Retest system. If test light illuminates, go to next step.
29. Connect test light between ignition feed circuit at CKP sensor harness terminal No. 2 (Green wire) and ground circuit terminal No. 3 (Black/Red wire). If test light illuminates, go to step 31 . If test light does not illuminate, go to step 32 .
30. Check for open or short circuit in Green wire between CKP sensor and PCM. Repair as necessary. Retest system. If problem was not found, go to step 33 .
31. Replace CKP sensor. Retest system. If problem is still present, go to step 34 .
32. Check for open or short circuit in Yellow wire between CKP sensor terminal No. 1 and PCM. If problem was not found, go to next step. If problem was found, repair Yellow wire as necessary.
33. Replace and reprogram PCM. See PROGRAMMING in SELF-DIAGNOSTICS - 2.2L article. Retest system.
34. Test for fuel contamination. If fuel is not contaminated, go to next step. If fuel is contaminated, clean fuel system as necessary. Replace fuel filter and verify all fuel injectors are delivering fuel. If problem was not found, go to next step.
35. Check for these possible conditions: Faulty camshaft timing belt. Leaking or sticking valves or rings. Excessive valve deposits. Loose or worn rocker arms. Weak valve springs. Leaking head gasket. Repair as necessary. See appropriate article in ENGINES. Retest system.

Passport 3.2L, Rodeo 3.2L, Rodeo Sport 3.2L & Trooper

1. Perform On-Board Diagnostic II (OBD-II) System Check. See ON-BOARD DIAGNOSTIC II (OBD-II) SYSTEM CHECK in SELF-DIAGNOSTICS - 3.2L & 3.5L article. After performing OBD-II system check, go to next step.
2. On Passport, Rodeo and Rodeo Sport, check IG. COIL fuse (15-amp) and ENGINE fuse (15-amp) located in dashboard fuse/relay block. Check ECM fuse (15-amp) located in underhood fuse/relay block in engine compartment. On Trooper, check IG. COIL fuse C-9 (15-amp) and ENGINE fuse C-8 (15-amp) located in dashboard fuse/relay block. Check ECM fuse F-13 (30-amp). If any fuse is blown, go to next step. If fuses are okay, go to step 4 .
3. Check for short to ground in appropriate circuits. See WIRING DIAGRAMS article. Repair as necessary. Replace any blown fuses.
4. Turn ignition off. Install fuel pressure gauge to fuel supply line test fitting. Turn ignition on. If fuel pressure is 43-55 psi (3.0-3.9 kg/cm 2 ) and holds steady, go to step 6 . If fuel pressure is not 43-55 psi (3.0-3.9 kg/cm 2 ) or does not hold steady, go to next step.
5. If no fuel pressure is indicated, go to «FUEL SYSTEM DIAGNOSIS»(ref-12119-S37790422272000121100000) under FUEL SYSTEM. If any fuel pressure is indicated, go to «FUEL SYSTEM ELECTRICAL TEST»(ref-12119-S09204602672000121100000) under FUEL SYSTEM.
6. Install Injector Tester (J-39021-2) at injector test connector and activate fuel injector. If fuel pressure drops, go to next step. If fuel pressure does not drop, go to step 18 .
7. Install fuel injector test light (noid light) at cylinder No. 2 injector harness connector. Turn ignition on and crank engine. If noid light blinks, go to next step. If light does not blink, go to step 24 .
8. Turn ignition off. Disconnect 11-pin harness connector from Ion Sensing Module (ISM) located on top of engine. Using a test light connected to battery voltage, probe each of the 6 exposed terminals while cranking engine. If test light flashes at each terminal, go to step 12 . If test light does not flash at each terminal, go to next step. WARNING: Use gray narrow Metripak flexible female connector from J-35616 Connector Test Adaptor kit (or equivalent) to access terminals and prevent terminal and connector damage.
9. Disconnect 4-pin ISM harness connector. Turn ignition on. Connect a test light between ground and 4-pin ISM harness connector Black/Orange wire (B+). Now connect test light between battery positive terminal and 4-pin ISM harness connector Black wire (ground). See WIRING DIAGRAMS article. If test light does not illuminate at both terminals, go to next step. If test light does illuminate at both terminals, go to step 11 .
10. Repair open in Black/Orange wire between ISM and IG COIL fuse (15-amp) in dashboard fuse/relay block, or in Black wire between ISM and ground. Test drive vehicle to confirm repair.
11. Replace ISM as necessary. Test drive vehicle to confirm repair.
12. Reconnect 11-pin ISM harness connector. Remove electrical connector from each ignition coil. Using a test light connected to battery voltage, probe each ignition coil harness connector at terminal that goes to ISM. See «IDENTIFYING IGNITION COIL TO ISM WIRES»(ref-12119-S39888037922000121100000) table. While cranking engine, observe test light. If test light does not flash at each ignition coil harness connector terminal, go to next step. If test light does flash at each ignition coil connector, go to step 14 . IDENTIFYING IGNITION COIL TO ISM WIRES Ignition Coil/Cylinder No. Wire Color 1 Red 2 Red/Black 3 Red/Blue 4 Red/White 5 Red/Yellow 6 Red/Green
13. Repair open circuit in appropriate wire between ignition coil connector and ISM connector. Test drive vehicle to confirm repair.
14. Turn ignition on. Ensure all ignition coil connectors are disconnected. Using a test light connected to ground, probe ignition feed circuit to each ignition coil harness connector Black/Orange wire. If test light does not illuminate at each terminal, go to next step. If test light does illuminate at each terminal, go to step 16 .
15. Repair open circuit in Black/Orange wire between appropriate ignition coil and IG. COIL fuse (15-amp) in underdash fuse/relay block. Test drive vehicle to confirm repair.
16. Ensure all coil connectors are disconnected. Using a test light connected to battery voltage, test secondary ground circuit of each ignition coil at harness connector (Black wire). If test light does not illuminate at each terminal, go to next step. If test light does illuminate at each terminal, go to step 18 .
17. Repair open circuit in Black wire between appropriate ignition coil and ground. Test drive vehicle to confirm repair.
18. Test for fuel contamination. If fuel is contaminated, clean fuel system as necessary. Replace fuel filter and verify all fuel injectors are delivering fuel. Test drive vehicle to confirm repair. If fuel is not contaminated, go to next step.
19. Remove any ignition coil. Install spark tester at spark plug end of coil. While cranking engine, check ignition coil for crisp, Blue spark. If weak spark or no spark is present, go to next step. If spark is okay, go to step 21 .
20. Replace faulty ignition coil. Repeat test from previous step for each ignition coil. Replace as necessary. Test drive vehicle to confirm repair.
21. Repeat test from step 19 for each ignition coil. Test one coil at a time, and reinstall each coil on its spark plug when testing is complete (DO NOT install screws). Attempt to start engine. If engine does not start, go to next step. If engine starts, install ignition coil screws and test drive vehicle to confirm repair.
22. Remove all spark plugs. Inspect spark plugs for fouling, loose or missing electrodes, or cracked insulators. Clean or replace spark plugs as necessary. If spark plugs are okay, go to next step.
23. Check for these possible conditions: Faulty or incorrect camshaft timing belt. Leaking or sticking valves or rings. Excessive valve deposits. Loose or worn rocker arms. Weak valve springs. Incorrect valve timing. Leaking head gasket. If problem was found, repair as necessary. See appropriate article in ENGINES. If no problem was found, go to step 25 .
24. Using scan tool, select ENGINE SPEED display. While cranking engine, observe scan tool. If RPM is indicated on scan tool, go to next step. If engine RPM is not indicated, go to step 34 . NOTE: If scan tool is powered by cigarette lighter socket and display goes blank while cranking engine, it will be necessary to power scan tool directly from battery.
25. Disconnect 7-pin Gray electrical connector at rear of air cleaner (below where air duct attaches to MAF sensor). Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at female side of connector, on Passport, Rodeo and Rodeo Sport (Red/Green wire) on Trooper (Red/Blue wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 32 .
26. Connect test light between female (PCM) side of 7-pin Gray electrical connector, on Passport, Rodeo and Rodeo Sport (Red/Green wire) on Trooper (Red/Blue wire) and each specified terminal. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table. Turn ignition on. If test light illuminates and stays on at any terminal, go to next step. If test light does not illuminate and stay on at any terminal, go to step 29 . 7-PIN GRAY CONNECTOR WIRE IDENTIFICATION Application Wire Color Injector No. 1 Green/White Injector No. 2 Green/Orange Injector No. 3 Green Injector No. 4 Green/Red Injector No. 5 Green/Black Injector No. 6 Green/Yellow
27. Turn ignition off. Disconnect PCM connectors. Connect test light between female side of 7-pin Gray electrical connector, on Passport, Rodeo and Rodeo Sport (Red/Green wire) on Trooper (Red/Blue wire) and each specified terminal. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table. Turn ignition on. If test light illuminates, go to next step. If test light does not illuminate, go to step 33 .
28. Repair short to ground in appropriate injector driver circuit. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table.
29. Connect test light between female side of 7-pin Gray electrical connector, on Passport, Rodeo and Rodeo Sport (Red/Green wire) on Trooper (Red/Blue wire) and each specified terminal. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table. Crank engine. If test light flashes at all terminals, go to step 31 . If test light does not flash at all terminals, go to next step.
30. Check for open in appropriate injector driver circuit. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table. Repair as necessary. If no problem was found, go to step 33 .
31. Turn ignition off. Connect ohmmeter between male side of 7-pin Gray electrical connector, on Passport, Rodeo and Rodeo Sport (Red/Green wire) on Trooper (Red/Blue wire) and each specified injector wire. See «7-PIN GRAY CONNECTOR WIRE IDENTIFICATION»(ref-12119-S42291316232000121100000) table. If resistance is about 12.5 ohms at all pins, go to step 8 . If resistance is not about 12.5 ohms at all pins, check for an open, shorted or faulty injector. Repair or replace as necessary.
32. Repair Red/Green wire(s) on Passport, Rodeo and Rodeo Sport, Red/Blue wire(s) on Trooper between PCM harness connector, PCM main relay (located in fuse/relay box in engine compartment) and 7-pin Gray electrical connector. See WIRING DIAGRAMS article.
33. Replace and reprogram PCM. See PROGRAMMING in SELF-DIAGNOSTICS - 3.2L & 3.5L article. Verify system is operating properly.
34. Raise and support vehicle. Disconnect Crankshaft Position (CKP) sensor connector. Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at CKP sensor harness wire (White wire on Passport, Rodeo and Rodeo Sport, Yellow/Red wire on Trooper). If test light does not illuminate, go to next step. If test light does illuminate, go to step 36 .
35. Repair open circuit or short to ground in wire (White wire on Passport, Rodeo and Rodeo Sport, Yellow/Red wire on Trooper) between CKP sensor and PCM harness connector.
36. Turn ignition on. Connect a test light between CKP sensor harness wire (White wire on Passport, Rodeo and Rodeo Sport, Yellow/Red wire on Trooper) and CKP sensor ground wire (Yellow/Black wire on Passport, Rodeo and Rodeo Sport, Green wire on Trooper). If test light illuminates, go to step 38 . If test light does not illuminate, go to next step.
37. Repair open or short to voltage in wire (Yellow/Black wire on Passport, Rodeo and Rodeo Sport, Green wire on Trooper) between CKP sensor and ground. Test drive vehicle to confirm repair.
38. Check for open or short in signal circuit (White/Blue wire on Passport, Rodeo and Rodeo Sport, Yellow wire on Trooper) between CKP sensor and PCM harness connector terminal F73. Repair as necessary. If circuit is okay, go to next step.
39. Replace CKP sensor. Verify system is operating properly. If system is still not operating properly, go to step 33 .

VehiCROSS

1. Perform On-Board Diagnostic II (OBD-II) System Check. See ON-BOARD DIAGNOSTIC II (OBD-II) SYSTEM CHECK in SELF-DIAGNOSTICS - 3.2L & 3.5L article. After performing OBD-II system check, go to next step.
2. Check IGNITION COIL fuse C-2 (15-amp) and ENGINE fuse C-3 (15-amp) in underdash fuse/relay block. Check PCM fuse EB-18 (40-amp) in underhood fuse/relay block. If any fuse is blown, go to next step. If fuses are okay, go to step 4 .
3. Check for short to ground in appropriate circuits. See WIRING DIAGRAMS article. Repair as necessary. Replace any blown fuses.
4. Turn ignition off. Relieve fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-12119-S09616014502000121100000) under FUEL SYSTEM. Install fuel pressure gauge to fuel supply line test fitting. Turn ignition on. If fuel pressure is 43-55 psi (3.0-3.9 kg/cm 2 ) and holds steady, go to step 6 . If fuel pressure is not 43-55 psi (3.0-3.9 kg/cm 2 ) or does not hold steady, go to next step.
5. If no fuel pressure is indicated, go to «FUEL SYSTEM DIAGNOSIS»(ref-12119-S37790422272000121100000) under FUEL SYSTEM. If any fuel pressure is indicated, go to «FUEL SYSTEM ELECTRICAL TEST»(ref-12119-S09204602672000121100000) under FUEL SYSTEM.
6. Install Injector Tester (J 39021-2) at injector test connector. Activate fuel injector. If fuel pressure drops, go to next step. If fuel pressure does not drop, go to step 10 .
7. Install fuel injector test (Noid) light at cylinder No. 2 injector harness connector. Crank engine. If test (Noid) light blinks, go to next step. If test (Noid) light does not blink, go to step 16 .
8. Disconnect ignition coil harness connectors. Turn ignition on. Connect a test light between ground and each ignition coil harness connector Black/Orange wire (B+). Now connect test light between battery positive terminal and each ignition coil harness connector Black wire (secondary ground). See WIRING DIAGRAMS article. If test light does not illuminate at both terminals of each ignition coil, go to next step. If test light does illuminate at both terminals of each ignition coil, go to step 10 .
9. Repair open ignition feed circuit (Black/Orange wire) or secondary ground circuit (Black wire) to ignition coil (s). Verify system is operating properly.
10. Test for fuel contamination. If fuel is not contaminated, go to next step. If fuel is contaminated, clean fuel system as necessary. Replace fuel filter and verify all fuel injectors are delivering fuel.
11. Remove any ignition coil. Install spark tester at spark plug end of coil. While cranking engine, check ignition coil for crisp blue spark. If spark is okay, go to step 13 . If weak spark or no spark is present, go to next step.
12. Replace faulty ignition coil. Go to next step.
13. Repeat test from step 11 for each ignition coil. Test one coil at a time, and reinstall each coil on its spark plug when testing is complete (DO NOT install screws). Start engine. If engine does not start, go to next step. If engine starts, install ignition coil screws and verify system is operating properly.
14. Remove all spark plugs. Inspect spark plugs for fouling, loose or missing electrodes, or cracked porcelain. Clean or replace spark plugs as necessary. If spark plugs are okay, go to next step.
15. Check for these possible conditions: Faulty or incorrect camshaft timing belt. Leaking or sticking valves or rings. Excessive valve deposits. Loose or worn rocker arms. Weak valve springs. Incorrect valve timing. Leaking head gasket. If problem is found, repair as necessary. See appropriate article in ENGINES. If no problem is found, go to step 17 .
16. Using Tech 2 scan tool, select ENGINE SPEED display. While cranking engine, observe scan tool. If RPM is indicated on scan tool, go to next step. If engine RPM is not indicated, go to step 26 .
17. Disconnect Gray 7-pin connector at rear of air cleaner (below where air duct attaches to MAF sensor). Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at female side of connector (Red/Blue wire). If test light illuminates, go to next step. If test light does not illuminate, go to step 24 .
18. Connect test light between PCM (female) side of Gray 7-pin connector Red/Blue wire and each specified terminal. See «FUEL INJECTOR CONNECTOR WIRE COLOR IDENTIFICATION»(ref-12119-S23564153642000121100000) table. Turn ignition on. If test light illuminates at any terminal, go to next step. If test light does not illuminate at any terminal, go to step 21 . FUEL INJECTOR CONNECTOR WIRE COLOR IDENTIFICATION Application Wire Color Injector No. 1 Green/White Injector No. 2 Green/Orange Injector No. 3 Green Injector No. 4 Green/Red Injector No. 5 Green/Black Injector No. 6 Green/Yellow
19. Turn ignition off. Disconnect PCM harness connectors. Turn ignition on. Recheck injector terminals. See «FUEL INJECTOR CONNECTOR WIRE COLOR IDENTIFICATION»(ref-12119-S23564153642000121100000) table. If test light illuminates, go to next step. If test light does not illuminate, go to step 25 .
20. Locate and repair short to ground in appropriate injector driver circuit. Verify system is operating properly.
21. Connect test light between PCM (female) side of Gray 7-pin connector Red/Blue wire and each specified terminal. Crank engine. If test light flashes at all terminals, go to step 23 . If test light does not flash at all terminals, go to next step.
22. Check for open in appropriate injector driver circuit. See «FUEL INJECTOR CONNECTOR WIRE COLOR IDENTIFICATION»(ref-12119-S23564153642000121100000) table. Repair as necessary. If no problem was found, go to step 25 .
23. Turn ignition off. Connect ohmmeter between male side of Gray 7-pin connector Red/Blue wire and each specified pin. If resistance is about 12.5 ohms at all pins, go back to step 8 . If resistance is not about 12.5 ohms at all pins, check for an open, shorted or faulty injector. Repair or replace as necessary.
24. Repair Red/Blue wire(s) between PCM connector, PCM main relay (located in fuse/relay box in engine compartment) and Gray 7-pin connector. See WIRING DIAGRAMS article.
25. Replace and reprogram PCM. See PROGRAMMING in SELF-DIAGNOSTICS - 3.2L & 3.5L article. Verify system is operating properly.
26. Raise and support vehicle. Disconnect Crankshaft Position (CKP) sensor connector. Turn ignition on. Using a test light connected to ground, probe ignition feed circuit at CKP sensor harness connector (Yellow/Red wire). If test light illuminates, go to step 28 . If test light does not illuminate, go to next step.
27. Repair open or short to ground in Yellow/Red wire between CKP sensor and PCM harness connector. See WIRING DIAGRAMS article.
28. Turn ignition on. Connect test light between CKP sensor harness connector Yellow/Red and Green wires. If test light illuminates, go to step 30 . If test light does not illuminate, go to next step.
29. Repair open or short circuit to voltage in Green wire between CKP sensor and ground. If no problem was found, go to step 31 .
30. Check for open or short in signal circuit (Yellow wire) between CKP sensor and PCM harness connector. See WIRING DIAGRAMS article. Repair as necessary. If circuit is okay, go to next step.
31. Replace CKP sensor. Verify system is operating properly. If problem is still present, go back to step 25 .

FUEL SYSTEM

FUEL SYSTEM PRESSURE RELEASE

Loosen fuel tank filler cap to relieve tank pressure. Remove fuel pump relay from underhood fuse/relay box. Start and operate engine until it stalls. Crank engine an additional 3 seconds.

Scheme 1

1. Perform On-Board Diagnostic II (OBD-II) System Check. See ON-BOARD DIAGNOSTIC II (OBD-II) SYSTEM CHECK in appropriate SELF-DIAGNOSTICS article. After performing OBD-II system check, go to next step.
2. Turn ignition off. Turn A/C off. Relieve fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-12119-S09616014502000121100000). Connect fuel pressure gauge. (Scheme 1) Turn ignition on (fuel pump will run for about two seconds). Use scan tool to command fuel pump ON. Note fuel pressure on gauge. If reading is not within specifications, go to step 17. See «FUEL PUMP PERFORMANCE»(ref-12119-S19674768682000121100000) table under FUEL SYSTEM DIAGNOSIS. If reading is as specified, go to next step. FUEL PUMP PERFORMANCE Application Specification All Models Operating Pressure 42-55 psi (3.0-3.9 kg/cm 2 ) Pressure Drop 3-15 psi (0.2-1.1 kg/cm 2 )
3. Fuel pressure will drop when fuel pump stops running. It should then stabilize and remain constant. If fuel pressure remains constant, go to next step. If fuel pressure does not remain constant, go to step 12.
4. With engine warmed up to operating temperature, turn ignition on and observe fuel pressure. Continue to observe fuel pressure while starting engine. Reading should drop a specified amount when engine starts. See «FUEL PUMP PERFORMANCE»(ref-12119-S19674768682000121100000) table under FUEL SYSTEM DIAGNOSIS. If reading drops by the amount specified, go to next step. If reading does not drop by the amount specified, go to step 9.
5. Test drive vehicle to determine if fuel pressure is dropping off during acceleration, cruise or hard cornering. If it is, go to next step. If it is not, check for improper fuel in vehicle. Drain and replace as necessary.
6. Check for restricted fuel filter or fuel line. Repair as necessary. If no problem was found, go to next step.
7. Remove fuel tank to inspect for restricted fuel pump strainer, leaking fuel line or incorrect fuel pump. Repair as necessary. If no problem was found, go to next step.
8. Replace fuel pump and test drive vehicle to confirm repair.
9. Disconnect fuel pressure regulator vacuum hose. With engine idling, apply 12-14 in. Hg. while observing fuel pressure gauge. If fuel pressure drops specified amount, go to next step. See «FUEL PUMP PERFORMANCE»(ref-12119-S19674768682000121100000) table under FUEL SYSTEM DIAGNOSIS. If fuel pressure does not drop specified amount, go to step 11.
10. Inspect fuel pressure regulator vacuum hose for leaks. Repair or replace as necessary. Test drive vehicle to confirm repair.
11. Replace fuel pressure regulator. Test drive vehicle to confirm repair.
12. Use scan tool to command fuel pump ON. After pressure builds up, turn off pump and clamp fuel supply hose with locking pliers that will not damage fuel line. Observe fuel pressure. If pressure remains constant, go to next step. If fuel pressure does not remain constant, go to step 15.
13. Inspect fuel supply hose for leaks and repair as necessary. If no problems were found, go to next step.
14. Remove fuel tank and inspect for leaking hose or in-tank fuel line. Repair as necessary. If no problem was found, go back to step 8.
15. Remove locking pliers from fuel supply hose, and clamp them to fuel return hose. Use scan tool to command fuel pump ON. After pressure has built up, turn off power and observe fuel pressure gauge. If fuel pressure reading remains constant, go back to step 11. If fuel pressure reading does not remain constant, go to next step.
16. Locate and replace any leaking fuel injectors. Test drive vehicle to confirm repair.
17. If fuel pressure indicated on gauge is above 55 psi (3.9 kg/cm 2 ), go to next step. If reading is not higher than specified, go to step 21.
18. Relieve fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(ref-12119-S09616014502000121100000) table. Disconnect fuel return line from fuel rail. Attach flexible fuel hose to fuel rail return outlet and put other end into a suitable container. Use scan tool to command fuel pump ON. Observe fuel pressure while fuel pump in running. If fuel pressure is within specified limits, go to next step. See «FUEL PUMP PERFORMANCE»(ref-12119-S19674768682000121100000) table under FUEL SYSTEM DIAGNOSIS. If fuel pressure is not as specified, go to step 20.
19. Locate and repair restriction in fuel return line. Test drive vehicle and confirm repair.
20. Visually inspect fuel rail outlet passages for restriction. Repair or replace as necessary. If no problem was found, go back to step 11.
21. If fuel pressure indicated is above 0 psi (0 kg/cm 2 ), go to next step. If fuel pressure is 0 psi (0 kg/cm 2 ), go to step 23.
22. Use scan tool to command fuel pump ON. Observe fuel pressure reading while slowly pinching off fuel return hose. If fuel pressure rises above 55 psi (3.9 kg/cm 2 ), go back to step 11. If fuel pressure does not rise above 55 psi (3.9 kg/cm 2 ), go back to step 7. CAUTION: DO NOT let fuel pressure rise above 60 psi (4.2 kg/cm 2 ), or fuel pressure regulator damage may result.
23. Use scan tool to command fuel pump ON. Remove fuel filler cap and listen for fuel pump operation. If fuel pump is running, go back to step 7. If fuel pump is not running, go to «FUEL SYSTEM ELECTRICAL TEST»(ref-12119-S09204602672000121100000).

IGNITION COIL

IGNITION COIL RESISTANCE - Ohms @ 68°F (20°C)

Scheme 2

IDLE SPEED

IDLE SPEED SPECIFICATIONS

IGNITION TIMING

Note. All models are equipped with electronic computer-controlled ignition system. Ignition timing is not adjustable.

SUMMARY

If no faults were found while performing BASIC DIAGNOSTIC PROCEDURES, proceed to appropriate SELF-DIAGNOSTICS article. If no hard codes are found in self-diagnostics, (if vehicle has self-diagnostic system) proceed to TROUBLE SHOOTING - NO CODES article for diagnosis by symptom (i.e., ROUGH IDLE, NO START, etc.) or intermittent diagnostic procedures.