Help!! Engine Miss

Dan Bennett · 06-18-2012, 08:58 PM

I've seen this situation three times. The first time was insufficient grounding, the second was a bad two step switch, and the third was a bad MSD rpm chip.

I think the original poster mentioned that the car is a Corvette; remember that these are wired differently from the factory as there are no natural body grounds with fiberglass. In the midyear cars even the radio antenna had to have a separate wire to the frame for it to work. That can sometimes also cause problems with RF interference to/from the MSD box as the fiberglass isn't any sort of shield. Again, in the stock versions a metal cage surrounded the ignition wires so the radio would work.

With the battery in the stock location behind the seat, the negative cable is very short as the frame is right there. I'd still check it carefully to make sure it's still internally sound enough to do its job.

Ben has done a remarkable job of running down all those little things that could cause the problem. Unfortunately, I've often had the experience that the longer you thrash on a problem, the farther you get away from what is really causing it.

I've seen some of the best minds in racing here in this thread, and it's amazing we still don't have a fix. Hang in there, Ben.

06-18-2012, 08:58 PM	#29
Dan Bennett Member Join Date: Jun 2007 Posts: 439 Likes: 853 Liked 595 Times in 136 Posts	Re: Help!! Engine Miss I've seen this situation three times. The first time was insufficient grounding, the second was a bad two step switch, and the third was a bad MSD rpm chip. I think the original poster mentioned that the car is a Corvette; remember that these are wired differently from the factory as there are no natural body grounds with fiberglass. In the midyear cars even the radio antenna had to have a separate wire to the frame for it to work. That can sometimes also cause problems with RF interference to/from the MSD box as the fiberglass isn't any sort of shield. Again, in the stock versions a metal cage surrounded the ignition wires so the radio would work. With the battery in the stock location behind the seat, the negative cable is very short as the frame is right there. I'd still check it carefully to make sure it's still internally sound enough to do its job. Ben has done a remarkable job of running down all those little things that could cause the problem. Unfortunately, I've often had the experience that the longer you thrash on a problem, the farther you get away from what is really causing it. I've seen some of the best minds in racing here in this thread, and it's amazing we still don't have a fix. Hang in there, Ben.