Thread: 94 Grand Prix after driving 20 miles it shuts down...???

My 94 Grand Prix with a 3.1 started shutting down the other day.
It seems like when I drive it around 20 miles it starts to jump like it's running out of gas then shuts down.
When this starts you can back off the gas and it's ok for a very short time and then the tach jumps and it shuts down.
I have checked the fuel pressure and it's fine. Even when it shuts down the pump primes when I try to restart.
After it shuts down, if it sets for a short time it will restart. If I set still and rev it up a few times the tach will start to jump then the low oil level light comes on and it shut down right away. This seems like and electrical issue and not fuel related. I'm thinking crank sensor or would one coil going bad cause this???
It has oil in the engine so I know the level is not down.
Any related experiences?

I agree with the pressure/level issue. It would drop the pressure under low rpms, it just happens so sudden that I thought maybe it was related to an electrical issue. I will check the pressure.
I have an extra coil pack that I saved from an early 3.1 swap (Monte carlo to Buick) I may just swap the coils and try it.
I am leaning to the crank sensor. I might just swap it out for piece of mind. Thanks!!

Well, the car left me setting again last night. I parked it overnight in Walmart parking lot and got a ride home. Just as I thought, this morning I had my wife drop me off and I drove home, which was 3 miles away. I replaced the coil paks today with a spare set I had in the shop. I let the car run in front of the shop for 45min until it started acting up again. Tach dropping when rev'd up and not shutting off but acting like it looses ignition fire for a split second then coming right back. I will be trying a crank sensor tomorrow and trying this all over again. I'll get this narrowed down soon.

Yesterday I installed the sensor behind the balancer along with a new front seal. I let the car run for about an hour and it started shutting ignition again. After looking into this a little closer I learned that the car has two crank sensors. The one behind the balancer provides a signal for the fuel injectors and the other sensor, located on the firewall side of the block, provides a signal to the coils.
While ordering this sensor I attempted to unplug it when I noticed something of a concern. The wires on the plugin were worn down to bare wires. The heat must have taken it's toll on the housing and melted it to nothing. I was surprised that it even ran.
I rewired the plugin with one new pigtail and also replaced the sensor.
I have drove it most of the day and it seems to be fine. I have added a photo of the wires and hope this gives others a direction if the same issues exist in their car. Thanks, Tim