Wagoneer L6-242 4.0L VIN M FI (1988)
Distributor Cap: Customer Interest
Ignition System - Engine Bucking/Surging
Models
1987-88 Comanche Wagoneer And Cherokee With 4.0L Engine
Subject
Engine Ignition Cross Fire
Index
DRIVEABILITY
Date
July 25, 1988
No.
18-53-88
P-2927
(C18-55)
SYMPTOM/CONDITION
Some 1987-88 Cherokee, Wagoneer and Comanche vehicles with the 4.0L engine may exhibit an engine ignition cross fire during vehicle operation. The
ignition cross fire will normally occur as a harsh bucking or surging condition.
NOTE:
THIS BULLETIN SUPERSEDES DISTRIBUTOR INSTALLATION PROCEDURES IN I.S. NOTES 31E, 40E, 42E (M.R. 244) AND
21E, 34E, 36E (M.R. 277).
DIAGNOSIS
Road test the vehicle with the MS 1700 Diagnostic Tester in the "State Display" test mode. Observe the engine vacuum and record the vacuum reading
when the cross fire condition occurs. An engine cross fire complaint will be repeatable at the vacuum range which was previously recorded regardless of
engine vehicle speed.
If a cross fire condition is diagnosed, proceed with the following repair procedure.
PARTS REQUIRED
Distributor Cap (1)
PN 33004024
REPAIR PROCEDURE
1.
Turn the ignition switch to the OFF position. Disconnect the battery negative terminal.
2.
Remove the coil wire and spark plug wires from the distributor cap.
