Rough Idle/Engine Stalls at Idle — Always
F2-33flowchart8 ROUGH IDLE/ENGINE STALLS AT IDLE — ALWAYS
Engine starts normally but stalls or vibrates excessively at idle in every condition.
NOTE
[TROUBLESHOOTING HINTS] (1) Air/fuel mixture too lean: Air leakage; Fuel injection control malfunction; Low fuel line pressure. (2) One or more fuel injectors clogged or not operating. (3) Low intake air amount. (4) Incorrect idle speed: Idle speed misadjustment; Idle air control malfunction. (5) One or more spark plugs not firing. (6) Low engine compression. (7) Volume air flow sensor stuck.
Rough Idle/Engine Stalls at Idle — Always
1
STEP 1: Is "00" displayed on SST with ignition switch ON? (Self-Diagnosis Checker, System Selector 49 B019 9A0, SELECT SW: A, 49 H018 9A1, Monitor Light) (page F2-73)
No
Diagnostic trouble code No. displayed: Check for cause (Refer to specified check sequence) (page F2-74)
Yes ("00" displayed): Go to next step
2
STEP 2: Are ECM terminal voltage 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 3: Disconnect high-tension lead at idle; does engine speed decrease equally at each cylinder?
Yes: Go to step 8
return to step 5
No: Go to next step
4
STEP 4: Is there fuel injector operating sound at idle?
No: Go to next step
STEP 5: Does battery positive voltage exist at fuel injector connector terminal A wire?
Yes: Go to step 6
5
STEP 6: Is strong blue spark visible at disconnected high-tension lead? (section G)
No
6
Check high-tension lead (section G). If OK, check distributor cap and rotor. If not OK, replace high-tension lead