Sputtering and now giving PO12 - 1995 Deville - 4.9

[bushjc]

Well after an almost year long battle with my Deville, I have decided to replace the PCM in the hope of curing her issue. After about $1000 in new parts and labor, I am no closer to resolving the issue than I was when I started. If anything, I am worse off.

Parts Replaced: Alternator, Fuel Pump, Fuel Filter, Fuel Pressure Regulator, ERG Valve, O Rings on all Fuel Injectors, Distributor, Plugs, Plug Wires, Idle Control Motor, Various Vacuum Lines, Cleaned Throttle Body.

A little history - In the beginning, the car would start without a problem. However, after maybe after a minute or so, it would seem as if it was trying to die (sputter) - pumping the gas did not have an effect. I could turn the car off and wait maybe 20 seconds and restart the car - Most of the time it would run fine after restarting until I shut it off again. During this time, I checked for trouble codes and never got one, not even History.

One day I went to start it and it would not turn over -nothing, not a click, nothing. However, this time I did get a SES indicator. After checking the code, I found it was "No Distributor Signal". Hence the replacement of the Distributor. After replacing distributor and clearing the code, the car would start again, but the original issue remained.

Then I purchased the ICM and installed - started the car and attempted to let it idle long enough to perform the Idle Learn Procedure. The car began trying to stall as before and I shut off the engine. When I attempted to restart, nothing. SES indicates the same code PO12 - No Distributor Signal.

I contacted the person who replaced the distributor, since it was supposed to be under a warranty. I am working to have that repaired/replaced.

I guess the only thing left to replace is the PCM. That brings me to the next question. What will be necessary in replacing this part? What has to be reprogrammed? Can I still use the original PROM chip? Or could that be the problem?

Any advice would be appreciated. I'd really like to get this car running. It is a shame that such a beautiful car is now being reduced to a large lawn ornament.

I have not checked the CAT, but I was told it was replaced before I bought the car. It should have less than 3k miles on it. BTW, I bought the car from a friend on my parents, so I feel the info is reliable and yes, I knew the car had this issue when I bought it.

I would rather not replace the PCM if I don't have to, but at this point I am not sure what to try next - Any thoughts or recommendations would be appreciated.

[KHE]

Replacing the PCM and throwing parts at it will accomplish nothing other than reducing the amount of cash you have. RARELY does the PCM fail. They are very durable units. If the No distributor signal is being set, you can be sure the PCM is not receiving the distributor signal.

You need to find out why the PCM is not receiving the distributor signal. Do you have a wiring diagram? If not someone with a 1995 shop manual should be able to post a schematic. I would check all the connections from the distributor to the engine harness for corrosion. It may just be corrosion in a connector that is interrupting the signal.