Could the tune have caused this to happen?

TRU 5.0

New Member
Sep 30, 2007
Nazareth, PA
I am still having issues with my 90 LX 5.0. :( This is the previous link:

I got a new dizzy ( JY and a new MSD), and the exact same thing happened - Car runs for approximately 15 minutes, then begins missing and eventually dies with a no spark condition, apparently with the PIP not functioning. It seems the spark gets weaker and weaker, then quits altogether. Also, car won't run with anything less than 20+ degrees of based timing. I verified the harmonic balancer is okay, and I have no vacuum leaks. This all started on the way home from the tune/dyno pull - I got 5 miles away from the shop and the car sputtered and died. Remember, it also ate an MSD TFI during one of the pulls at the shop. Previous to this, the car ran great since the H/C/I install. I also checked the grounds at the back of the block and for the ECM - all appear to be connected.

The question is: Is there something the tune could have done to the ECM which is causing my problems? It sounds ridiculous to say, but everything was fine prior to the tune, and now the car won't run. I unfortunately don't know enough about the spark and /or fuel tables to determine if this is even possible.

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