Wife and I went out for a cruise tonight. We drove around for about 45 minutes and then decided to go watch the sun set over the lake. Parked the car and shut the engine off for about 20 minutes.

When I restarted it, there was an immediately noticeable missfire. I backed the car up and started driving home. The miss was present constantly - in park or in gear, idling, under acceleration, cruising, you name it.

I was anticipating having to troubleshoot the miss when I got home, but a few minutes later it cleared up and drove smooth as silk the rest of the way home.

The car is an '89 IROC L98.

The only thing that was out of the ordinary was that when I parked at the lake, the parking lot was on a slope and we ended up parked with the nose of the car slightly elevated.

Any ideas?

 

I'd check your plug wires for any abnormal wear. When I got my car, the jacket had rubbed on the body and was occasionally arcing to the frame instead of the plug. Could have also been a spot of bad gas.