94 NA daily driver.

Car starts and runs but while running the engine cuts out. Check engine light flashes when engine cuts out but its only for a split second then everything comes back. Certainly feels like a short somewhere that comes and goes but it's consistent.

Also the tach is jumpy moving all over the place. Sometime at zero, even with the car running, and sometime working correctly and jumping between these two positions. When the check engine light comes on and the car dies for a moment the tach dies also.

Mechanic friend of mine did some work and thinks it's in the gauge cluster. When it's disconnected the car runs perfect. When we plug it back in the problem reappears. He thinks we need a new one, or get the old one checked/reconditioned.

So does any of this make sense? Never touched the cluster or the electrical system. Do they just die? Anyone seen/heard of anything like this? Are we chasing this in the wrong direction?

Thanks,

 

* Are you the first and only owner of the car?
* Was any electrical work done on the car?
* Is it completely stock, or are there any mods to the engine or the electrical system - alarm, aftermarket stereo, etc?
* Was the engine ever removed for any reason?

Also, remove the ignition surround (plastic covers behind the steering wheel - 3 screws) along with the cover just above the pedals (2 screws) and wiggle the wires going to the ignition switch while the engine is running.
If the engine stumbles or dies, check the ignition switch connector terminals. I have seen them corrode and suffer heat damage, leading to intermittent contact failure, because every Tom, Dick and Harry taps into the ignition switch wiring for whatever electrical needs and overloads the hell out of the rated capacity, leading to the sort of problem you are describing.

A nervous (jumpy) tach usually points to bad ground. Check the engine ground strap, ground point at the rear of the PPF, and those ground connections just behind and below the throttle body. Some get overlooked when reinstalling the engine or related components.

Gently tap on the large green relay in the underhood fuse panel while the engine is running. That is the man relay. They seldom go bad, but hey, give it a shot.

 

Thanks for the quick reply.

Only owner. No mods or engine work. Already changed the plugs, leads, coil packs and entire ignition switch. Also cleaned up some grounds.

it’s really strange. Feels like something so simple but no one can nail it down.

 

Have a good look at not only the main relay but the plugs on the back of the fuse box that that relay is in. Ive had one back out with similar results. Fredb