PROM - Lack of High Speed Power
90chevy15Number: 89-266-6
Section: 6
Date: September 1989
Corp. Bulletin No.: 936521
Subject: LACK OF POWER AT HIGH SPEED
Model and Year: 1989 B CAR WITH 5.7L (VIN CODE 7) EN
Some 1989 B-cars with the 5.7L V8 engine may exhibit lack of power at high speeds. Additionally, these vehicles MUST be operated in 4th gear (NOT 3rd gear) at high speeds to maximize powertrain performance. If the vehicle does not shift into 4th gear at Wide Open Throttle, refer to Dealer Service Bulleltin No. 89-226-7A, dated August 1989 for important information concerning a 3-4 upshift valve package.
If the vehicle performance cannot be improved by following normal diagnostic procedures, the following PROM may be used along with the 3-4 upshift valve package per the above bulletin.
Engine Trans New Service PROM New Scanner ID Broadcast Code
5.7L Auto 16144294 4301 ATJP
Parts are expected to be available on October 11, 1989. Until then, normal part orders will not be accepted by GMSPO. Only verifiable emergency VIP orders will be accepted. SPO will make every effort to obtain parts. All parts will be placed on 400 control to waive VIP surcharges. However, the part will be shipped premium transportation at dealer's expense. All other order types will be canceled as incorrectly ordered while the 400 control is in place.
Labor Operation Number: T0500
Labor Time: .5 hour