Yo guys, some help please. Car is an 88 IROC with the LB9 and T5. Recently, when I'm driving down the freeway at about 60, the engine will momentarily cut out, then come back. It's just for an instant. You can see the tach needle flick down when it happens. It's happening now every couple of minutes. The SES light is not on. Engine starts easily and idles smoothly.

Ideas? Thanks.

 

You're momentarily losing ignition, either the power to it or a circuit within it.

Since it starts and idles fine, the first is a pretty good guess. Look for loose or poor connections to the ignition. Especially true if it starts and idles smoothly when hot.

However, could still be a circuit within the ignition. Factory coil & module are know weak actors.

 

Hey there, I had a simular problem. I replaced my ignition switch nd so far I haven't had any more problems with that happening.

 

Thanks guys. I suspected it was either ignition or injection or maybe computer.

I'll look for connection issues in the wiring. It does start and idle smoothly when hot, and all other times as well. Fires right up when stone cold.

If I have to replace the (external hei) coil or module, should I go with AC Delco or aftermarket? MSD? But they don't make the module with enough pins. Can you even still get Delco parts for a car this old?

 

Hey tremo, its Travis here, Knowing your car, I doubt its a lose connection, sounds either like the coil or ingition module is cutting out.

I can hook you up with a stock replacement MSD coil.

it does have the two connectors for your stock harness.