Engine - Rough Idle/Surge Hot
88pontiac13Bulletin Number: 88-6-68
Reference Number: 836530
Publish Date: 8/88
Subject: ROUGH IDLE/SURGE HOT
Models
Affected: 1988 FIREBIRD WITH 5.0L AND 5.7L ENGINE
Some owners of 1988 Firebirds equipped with V8 PFI engines (VIN Codes F and 8) may experience rough idle at high ambients and surge on driveaway following a hot soak or extended idle. This condition may be caused by interaction between the canister vent and the air cleaner inlet. An indicator of this condition is low Block Learn Memory (BLM) and integrator during an extended idle indicating that the ECM is lowering the base pulse width (injector on time) to compensate for an external source of fuel vapors.
This condition may be addressed by installation of a canister vent harness, P/N 10105257. A clip, P/N 10105274 will also be required to complete the installation.
Parts are currently available from GMSPO.
The harness should be installed as shown in the illustration. The perpendicular line should be connected to the currently open vent port on the canister. The shorter of the two remaining ends should be tucked into the existing hole in the inner fender as shown. The third (longest) end should be pushed through clip, P/N 10105274 until it extends approximately 1 inch beyond the edge of the clip. The clip should then be attached under the existing facia brace bolt as shown. The facia brace bolt can most easily be accessed from underneath the vehicle.
Warranty Information
Labor Operation: T1371
LaborTime : .3 Hours