f-150country

my brother has an 88 dynasty that once in a while dies on the road and will not start for about 5 minutes and then will start and run just fine. It does not happen all the time just whenever it feels like it. New coil, wires and map sensor. Any ideas aould be greatly appreciated.

denisond3

You will get better guesses if we know which engine it has; the 4 cyl with TBI, or the 6 with MFI?
When you say it wont start - do you mean starter cranks the engine right away - but it doesnt fire up? Or does the engine not crank over for the first few minutes?
If the former, then in both cases I would personally suspect the ignition modules if they are original. And if its the 4 cyl; can you see fuel spraying from the TBI injector with the air cleaner off? If its the 6 cyl, is there a way to check fuel pressure in the fuel rail? When was the last time the fuel filter ws changed?
If the driver carries a spare spark plug along, then the next time it dies on the highway, pull a plug wire off and put the spare spark plug into it, lay the plug on the metal of the motor, and crank the engine with the starter. Look for a nice blue spark.

f-150country

Sorry bout that. It is a 6 cyl and it does crank but does not fire. I thought about the fuel filter but that just did not seem to make any sense, Why does it just die. It doesnt seem to chug or anything like it is out of fuel it just shuts down. The same for the spark, it doesnt seem to miss or anything. Could it still be the ignition module?

denisond3

I have an 87 Dodge minivan, whose only ignition module is inside the distributor. It has been replaced twice (in 208,000 miles), and both times it would quit suddenly while underway, but would restart when it had cooled off for a few minutes. Except...one of the times I didnt replace it soon enough, so had get the new module and walk back to do the replacement at the side of the road.

f-150country

I talkde to my brother and he said that it is showing codes 12 and 25. according to what i found 12 means that the battery has recently been disconnected which i dont know why there would be a code for it and 25 says 'AIS wiring is open/shorted'. Is AIS stand for automatic ignition system? I looked into an ignition module and i seen that they aint cheap so i would like to be sure before I tell him to get one. Or would i be safe to pull one from a junkyard?

denisond3

Sorry I dont know what AIS means - I dont have a dynasty. My 87 dodge Omni predates the "check engine light" systems, and our 97 Neon has different codes. Usually the '12' just means it is beginning to list the codes it had. But being an 88, the Dynasty might not use the same codes as the later OBD-II compliant codes.
I would certainly try getting one from a junkyard, and hope that the module wasnt the reason it got junked. At least you will be able to swap it into the car and see if it works at all. The most difficult problems to fix are usually the electrical ones that are intermittent.

f-150country

talked to a guy at a shop and he said that AIS is probobly air idle speed