TROUBLESHOOTING GUIDE — CRANKS NORMALLY BUT HARD TO START — ALWAYS (continued)
F2-28flowchartCRANKS NORMALLY BUT HARD TO START — ALWAYS (steps 6-11, continued from F2-27)
1
STEP 6: Disconnect idle air control valve connector at idle; Does engine speed increase? (page F2-99)
No
Replace idle air control valve (page F2-95)
Yes — Go to next step
2
STEP 7: Are ECM terminal voltages OK? 1C-Starter signal; 2E-Engine coolant temperature sensor; 3D-Sensor ground (page F2-141)
No
Check for cause (page F2-141)
Yes — Go to next step
3
STEP 8: Connect data link connector terminals F/P and GND by using jumper wire; does engine start normally?
Yes
Check fuel pump relay (page F2-113). If OK, repair or replace wire harness. If not OK, replace relay
No — Go to next step
4
STEP 9: Connect System Selector to data link connector and set Test Switch to "SELF TEST"; is ignition timing at idle correct after warm-up? (page F2-70). Ignition timing (BTDC): 9—11° {10 ± 1°}
No
Adjust ignition timing (page F2-70)
Yes — Go to next step
5
STEP 10: Is engine compression correct? Engine compression (Minimum): 981 kPa {10.0 kgf/cm2, 142 psi}-300 rpm
No
Check engine condition: Worn piston, piston rings, or cylinder wall; Defective cylinder head gasket; Distorted cylinder head; Improper valve seating; Valve sticking in guide
Check engine condition: Worn piston, piston rings, or cylinder wall; Defective cylinder head gasket; Distorted cylinder head; Improper valve seating; Valve sticking in guide
Yes — Go to next step
STEP 11: Try a known good ECM and check if condition improves (page F2-141)