Engineering Analysis · STALLING · Opened 1988-03-10 · Closed 1989-10-03
Investigation
Action number
EA88025
Type
Engineering Analysis
Open date
1988-03-10
Close date
1989-10-03
Manufacturer
Chrysler (FCA US, LLC)
Affected makes
JEEP
Affected components
VEHICLE SPEED CONTROL:LINKAGES
Affected model years
1987
Affected (make, year) variants
3
Summary
ANALYSIS OF INFORMATION FROM MANUFACTURER:THE MULTI-POINT INJECTIONSYSTEM (MPI) USED ON THE SUBJECT VEHICLES HAS HAD WIRING HARNESS FAILUREAND FAILURE OF THE CRANK POSITION SENSOR (CPS).BOTH FAILURES HAVE A HIGHFREQUENCY AND ARE THE SUBJECT OF JEEP TASK FORCES.NUMEROUS MODIFICATIONSTO BOTH ITEMS HAVE BEEN MADE.ANALYSIS:THE STALLING PROBLEM IS SEMI-INTERMITTENT, THAT IS WIRINGHARNESS FAILURE IS MOST LIKELY TO OCCUR UNDER THOSE CONDITIONS WHERE THEHARNESS IS DISTURBED (CORNERING AND ROUGH ROAD).CPS FAILURE CAN OCCUR ANYTIME, BUT FAILURE APPEARS TO BE ACCENTUATED BY HIGH UNDERHOOD TEMPERATURES(EXHAUST MANIFOLD LEAKS, ETC.) AND DISTORTION OF THE CPS HOUSING FROMEXHAUST HEAT DAMAGE OR THERMAL FLEXING.BOTH CONDITIONS RESULT IN NOSIGNAL.STATUS:RECOMMEND OPENING EA AND SENDING A MORE REFINED IR.===