Safari Van M V6-262 4.3L VIN W CPI (1992)
PROM - Programmable Read Only Memory: All Technical Service Bulletins
PROM - Detonation or Spark Knock On Acceleration
BULLETIN NUMBER: 92-6E-128
SECTION: 6E
NUMBER: 1
CORPORATE REFERENCE NUMBER: 236511
DATE: September 1992
SUBJECT:
DETONATION/SPARK KNOCK (REPLACE PROM KIT)
MODELS:
1992 M/L/G VANS WITH 4.3L TBI V6 ENGINE (VIN Z) RPO LB4
CONDITION:
Some 1992 4.3L RPO LB4 engines may exhibit sustained detonation or spark knock on acceleration, while climbing hills or pulling trailers.
Note: Some "burst" detonation for short periods of time at tip-in acceleration or at shift points is normal.
CAUSE:
The ESC (Electronic Spark Control) system is not pulling out enough spark to keep detonation noise below audible levels. The ESC system will protect
the base engine components from damage that could result from severe detonation.
CORRECTION:
Replace calibration PROM (Programmable Read Only Memory) with service PROM kit, see chart.
PARTS AVAILABILITY:
Parts are available. In case of limited inventory, parts will be placed on 400 control to waive VIP surcharges. Only verifiable emergency VIP orders will
be accepted. GMSPO will make every effort to obtain parts. However, the part will be shipped premium transportation at dealer's expense and all other
order types will be placed on backorder until the 400 control is removed.
WARRANTY INFORMATION:
Labor Operation:
T-0500
Labor Time:
0.5 Hr
