Brady

iTrader: (3)

Long story, but I ended up with one, and it's not working - can't connect with LT1 edit. car will crank and fire occasionally, but not run..

I just found out that the PCM was from an Impala.. Is that the problem?

The car will start and run fine with a known good PCM.

thanks

Camaroholic

iTrader: (1)

Yes, it will.

My spare PCM is a L99 (Caprice) PCM.

I had to replace the knock module with a Z28 unit.

I also had to reprogram the PCM with my Z28's file to make it work.

But other than that, it did indeed work just fine.

Think of it this way...

Both PCMs are GM service number 16188051. Hardware wise, they are exactly the same. The Impala / Caprice uses 2 knock sensors - so the module is different. Also, the program inside the PCM is different (obviously), but the PCM can be reflashed with a Z28 (or whatever you want) program.

Can you connect to it with a scan tool?

-Andrew

Camaroholic

iTrader: (1)

And more info...

You say you "ended up with one".

And the car will crank, and not run.

That, to me, says the PCM may be no good. My car (it was bone stock at the time) would run with the L99 PCM. It didn't like it very much, SES light was on because of the L99 knock module, but it did run. I did this outside the front door of the junkyard I bought the PCM from (might as well test it while I was there, right ). My Diacom did connect to the PCM at that time also (running the L99 program - this was in the alpha testing of LT1Edit days... before it was even called LT1Edit).

When you turn on the key, do the fans kick on (assuming you've replaced the knock module)?

I'm wondering if it was programming-interrupted and someone shelved it. If it was, then it will crank, maybe fire, but not run (limp mode). If the fans kick on, and you can't connect to it with a scan tool or LT1Edit, then it may have been flash-corrupted.