Chrysler Repair: Chrysler Cirrus, fuel pump filter, battery clamps

Question
Hello.I have a Chrysler Cirrus 1995.lxi..v6...It will just cut off on you while driving..it doesnt matter if its an hour or 5 min. and its driving me upthe wall!  Since March, I have replaced everything necessary it seems...Fuel pump/filter, distributor, new belts, water pump, starter.   I cant seem to find anyone who can figure this one out.. I did the code test by turning the ignition on off on off then on again and it said 1...2...5..5.. whichis wierd cause i didnt read those codes in the book.. someone said it was my PCM...PowerContolModule.. what do you thinkit could be..

Answer
Hi Audrey,
The 12 code means that sometime in the past 50-100 igniton off-on-off cycles the power to the PCM was disconnected. If you haven't disconnected the battery in that number of cycles then that is a possibly relevant code. It might mean the battery clamps are loose on the posts, or the posts are oxidized and need to be cleaned up, or there is a loose ground connection from the - post of the battery (check all the wires that are associated with the -post clamp and make sure they are all attached to shiney metal surfaces and clamped tightly, including the one to the body near the battery tray and the one at the strut tower on the driver's side, and the one to the engine cylinder head at the rear.
The 55 just means "end of readout". I would also suggest that the next time this happens you should be prepared to test whether you have lost your spark or not, and weather you hear the fuel pump run for about 1 second when you first turn the ignition switch to run (listen for that sound so you know what it sounds like when things are o.k.).
To be ready for spark test:
Nonetheless, the best thing to do is to have a spare spark plug with you and then when the car dies to remove one of the rubber spark plug connector caps located on the valve cover closest to the front of the car (there are 3); turn the rubber boot 1/2 turn and pull straight back out of the cover, don't pull on the wire however. Once the connector comes out insert the spare plug and hold the assembled plug and rubber fitting by the rubber but positioned so that the metal threads of the test spark plug are firmly in contact with the engine head or similar metal surface of the engine block. Then recruit a helper to use the ignition key to crank the starter motor. You would watch to see whether or not you are getting a spark jumping across the gap at the tip of the plug. You would then know if the problem is likely due to the ignition system (no spark) or the fuel system (spark present). You should try this self-diagnosis procedure at home using an old spark plug that is for the car engine (or buy a new one specifically for your car though they are a bit expensive because they are supposed to last for 100,000 miles, mainly because the ones at the rear valve cover are a major effort to replace, unfortunately).
That way you can be sure that you are doing it correctly when the need arises. When you remove the rubber cap, use a tool to get around and under it rather than pulling on the rubber wire which would likely damage the wire's connection to the rubber cap and internal contact.
The other thing to do is to regularly test the engine controller memory for the appearance of new fault codes. Let me know if anything other than a 55 is present or shows up and we'll take it from there. A no start without a code is one of the toughest problems to remediate.
You will want to do the test of the engine with the spark plug when it won't start because that is very useful for diagnosing what could be the problem at the time it is actually present.
Roland