Rough Idle/Engine Stalls at Idle — When A/C, P/S, or E/L ON
F2-39flowchartReferences A/C, P/S, and E/L (electric load) operating conditions.
NOTE
B+: Battery positive voltage
11 ROUGH IDLE/ENGINE STALLS AT IDLE — WHEN A/C, P/S, OR E/L ON
Engine stalls or vibrates excessively at idle when A/C, P/S, or E/L ON. A/C, P/S, headlights, blower fan, and electric coolant fan operate normally. Idle condition is normal when A/C, P/S, and E/L are OFF.
NOTE
[TROUBLESHOOTING HINTS] (1) Idle air control system malfunction.
Rough Idle/Engine Stalls at Idle — When A/C, P/S, or E/L ON
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: Does SST Monitor Light show that switches operate correctly with ignition switch ON? (page F2-92)
No (Light does not turn ON or OFF)
Light does not turn ON or OFF with specified switch: Check for cause (Refer to specified check sequence) (page F2-93)
No (Light always ON)
Light always ON: Check wiring between ECM terminal 1D and SST
Yes: Go to next step
3
STEP 3: Is ECM terminal 1I voltage OK? (page F2-141) Voltage: Battery positive voltage (at idle)
No
Check for short circuit in wiring between data link connector terminal TEN and ground
Yes
4
Try known good ECM; and check if condition improves (page F2-141)