My 92 Deville has been giving me problems recently...I found the following codes via the digital dash: E12, E41, E52, E91. It stalls when coming to a stop, runs rough intermittently, engine surges. It is a very unpredictable condition. Some days it runs perfect. Gas mileage increasesand gives the impression that everything is normal and fine. Then out of the blue, it acts up again. Mileage falls off, engine runs rough, etc..... I've changed dist cap, rotor, plugs, and wires--made some difference. I'm ready to change the fuel filter and clean out the throttle body. I am hoping the codes are a good clue. Can someone give the tell-tale diagnosis from the codes? Thanks in advance for your advice.

 

12 - no distributor signal
41 - no camshaft position sensor signal from ignition control module
52 - PCM keep alive memory reset
91 - PRNDL switch or transmission range switch signal problems

12 and 41 are the problem ones for your condition.

 

Thanks for the info. I am still limping along....in spite of the trouble codes. Is all this pointing to a defective Ignition Control Module? For as long as I have had the car, almost 5 years, the ICM has never been replaced. Thanks for your added support.

justtalkin