Engine - Stall After Cold Start or Hesitation
89pontiac06Number
86-6-84 Date 3/89
Subject: HESITATION/ENGINE STALL AFTER COLD START (NEW SERVICE PROM P/N) 1986 6000 W/2.8L (VIN W) AND AUTO. 3-SPD. TRANSMISSION
Some owners of 1986 6000 models with 2.8L multi port fuel injection (MPFI) engine and a 3-speed automatic transmission may experience a stall after cold start or an engine hesitation during a cold driveaway.
To service this condition, which generally occurs at approximate temperatures of 50 - 70 degrees Fahrenheit, complete the diagnostic procedures per Section 6 of the Service Manual. Specific attention should be given to the following items and repair as required:
1. Loose or leaking air duct between mass airflow (MAF) sensor and throttle body.
2. Low base idle air rate.
3. Openings in the EGR transfer tube.
If the condition persists, replace the PROM with one of the following service PROMS, which may be obtained from GMSPO. (See the following chart).
IMPORTANT: The new service PROMS are for 6000 models with a 2.8L port fuel injected engine and a 3-speed automatic transmission.