My 97 SS was running fine, a week after swapping on a new Opti, and now it won't restart. The fuel pump is priming, and the engine will turn over but not start. There is no fire at the plugs or at the coil. I replaced the coil and module with known good ones, and still there is no spark. I even removed the Opti to be sure the drive pin was properly engaged. I connected a scanner and it would not even boot up (its an inexpensive Actron, but I verifed it works on another car). The car was coding before (for the rear O2s) and possibly something else, but was running and starting fine.The Service Engine light and other warning lights come on when the ignition is turned on. It did have a problem I haven't seen before, though; after shutting the car off, it would run on for a couple seconds...not like the "dieseling" you hear on some older carbureted stuff, but more like the ignition was taking a few seconds to respond. Not sure if that is related, but I'm betting it is now that the ignition system isn't functioning at all. Any ideas? Thanks guys!

 

Was the Actron an OBD-II scanner? What other car did you check it on?

Toasted PCM's are sort of rare.

 

Yes, its an OBD-II scanner...I tested it on a 2001 Z28. I forgot to mention, I have also checked all the fuses (both locations). I have a spare OBD-I computer that I will put in today to see if it cures the problem before buying another one (its calibrated for my old motor).

 

I thought the 97's had an igintion modual that was seperate from the PCM? I'll check tonight.

 

Well, I assume the former OPTI was shot and that is why you swapped it out for a new/different one?? I would ask how the first one died and then entertain the thought that maybe the new one is toasted also.

Just a thought.

 

Yes, it was shot...the car sat up for about two years in a damp basement, and moisture had gotten to it. The car ran ok most of the time, but would occasionally buck and make all kinds of noise (backfires, etc). It would always restart though, at least after a few tries. The new Opti made a huge improvement, and the car was running fine for nearly a week. I feel sure its not the opti. BTW the ignition module isn't in the PCM, its above the coil. Since the scanner won't show anything (it wont even boot up), and there is no voltage between the two terminals on the ALDL that Actron says to check, I'm betting it is the PCM. Its not the original PCM in the car; the car was at one time equipped with ported heads, a GTP6 cam, and other goodies, andwas converted to OBD1. When I put it back stock, I got the OBDII PCM off Ebay. No telling what it has been through.

 

Just in case. I have two obd II pcms in my living room right now. One's out of my 96 that had 68,000 miles on it and the other is a core I forgot to return to Ion. Feel free to PM me if you want to buy one off me.

Mike