CHUGGLE/DETONATION (REPLACE PROM)

SUBJECT: TIP-IN HESITATION, SAG, LONG CRANK TIMES WHEN COLD, AND/OR DETONATION, CHUGGLE

MODELS AFFECTED: 1991-1992 BROUGHAMS (RWD) WITH 5.0L OR 5.7L TBI

This bulletin supersedes T-92-61A which should be discarded. This bulletin is being revised to add an updated service PROM for 5.7L vehicles with detonation or chuggle symptoms and to clarify information from the previous bulletin.

Some 1991-1992 Broughams (RWD) with 5.0L (L03) or 5.7L (L05) TBI may experience one or more of the following driveability conditions:

o Tip-in sag

o Tip-in hesitation

o Long crank time when cold

o Detonation

o Chuggle (this pertains to 5.7 engines only)

To repair the above conditions refer to the chart listed below and install the appropriate component(s) for the specified vehicle with the appropriate model year and engine classification.

MODEL YEAR 1991 1992 Service Ser. PROM Broadcast Service Vehicle Engine P/N I.D.* Code P/N ------- ------ ------- --------- --------- -------- D Fed/Cal 5.0 PROM 16160477 0531 AXHR #ESC 16175099 #ESC 16175099

Service Ser. PROM Broadcast Service Vehicle Engine P/N I.D.* Code P/N ------- ------ ------- --------- --------- ------- D Fed/Cal 5.7 PROM 16195060 5111 BHHM Same as 91

Service Ser. PROM Broadcast Service Vehicle Engine P/N I.D.* Code P/N ------- ------ ------- --------- --------- ------- D Export 5.7 PROM 16195064 5121 BHHN Same as 91 (leaded)

* ECM PROM I.D. can be read with a scan tool connected to the ALDL connector.

# Refer to Section 6E2-C5 of the appropriate Service Information Manual for proper installation of the Electronic Spark Control (ESC) module.

Parts are currently available from GMSPO.

WARRANTY INFORMATION VEHICLE SERIES -------------------- Operation -------------- Operation Description Number C D E K V --------------------- --------- ------------------------------- MEM-CAL - Replace J6364 .4 ESC Module - Replace J4438 .2

General Motors bulletins are intended for use by professional technicians, not a "do-it-yourselfer". They are written to inform those technicians of conditions that may occur on some vehicles, or to provide information that could assist in the proper service of a vehicle. Properly trained technicians have the equipment, tools, safety instructions and know-how to do a job properly and safely. If a condition is described, do not assume that the bulletin applies to your vehicle, or that your vehicle will have that condition. See a General Motors dealer servicing your brand of General Motors vehicle for information on whether your vehicle may benefit from the information.