False Code 53 And/Or Engine Dieseling
WARNING: This page does not describe the selected car, but rather 28 other vehicles, including the 1984 Pontiac Phoenix, 1984 Pontiac Parisienne, 1984 Pontiac Grand Prix, 1984 Pontiac Firebird, and 1984 Pontiac Bonneville. However, it is still accessible from the selected car via links, so may be relevant.
Some early production Ciera models with 3.0L (VIN E) engines may show engine dieseling, or a trouble code 53 being set during extended deceleration of more than 10 seconds. If code 53 is stored in ECM memory yet "No Trouble Found" is indicated, the PROM broadcast code should be checked.
A PROM with a code of CKP should be replaced with a PROM (16042776) with code DPY for Federal models. A PROM with code CKR should be replaced with a PROM (16042782) with a code DPZ for California models.