Engine Controls - Reduced Performance and Power

91pontiac03

Bulletin Number: 91-6-27
Reference Number: 136504R
Publish Date: 3/91


Subject: REDUCED PERFORMANCE AND POWER (REPLACE ESC MODULE WITH NEW PART)


Models
Affected: 1991 TRANS SPORT WITH 3.1L (VIN D)


Condition:

Some owners of 1991 Trans Sport models with 3.1L (VIN D) engine may comment of reduced performance and power on vehicles built prior to VIN MT212419.

Cause:

The ECM (Electronic Control Module) may be incorrectly retarding the engine because of incorrect signal from ESC (Electronic Spark Control) module.

Correction:

If normal diagnostics as described in your shop manual (Section 6E2-B-3) do not correct this condition, replace ESC module with P/N 16126761 (Broadcast Code ANRZ).

Parts are currently available from GMSPO.

Use applicable Labor Operations And Times.