Comanche 4WD L6-242 4.0L VIN M FI (1987)
Idle Speed: All Technical Service Bulletins
Engine - Low Idle Speed/Stalling
39E428
OCTOBER 1987
1987 COMANCHE VEHICLES WITH 4.0L ENGINE
ENGINE
Attention: Workshop, Parts Department
LOW IDLE SPEED
Some Comanche vehicles equipped with a 4.0L engine may exhibit a start, run and then stall condition during hot ambient temperatures. This condition
could be caused by either an injection system malfunction or an incorrect idle speed setting.
Service correction for this condition requires an injection system test with a MS 1700 tester and repair of any malfunction detected via the tester. If no
malfunction exists or the condition persists after repair, perform the following idle speed adjustment procedure.
ADJUSTMENT PROCEDURE
The engine must be at normal operating temperature, automatic transmission in the PARK position, manual transmission in NEUTRAL and all electrical
accessory switches in the OFF position.
1.
Connect a tachometer to diagnostic connectors D1-1 (+) and D2-7 (-).
