I recently acquired a 1996 coupe with 140k miles to use as a driver. Ran fine the first thousand miles, but then began stalling, sometimes to the point of dying. While idling or driving you could feel a distinct skip and the tach will drop. Then it pops back up and will run fine for a while. A few times it just shut off, almost as if the key was turned off when coming to a stop. I had a code occur for ICM multiple times (weak pulse/low signal) and EGR. If I cleared the CEL it would pop right back on when started with the ICM code.
I swapped the one off my '94 and drove it around a little. Runs better, no codes/lights yet, but still has the occasional skip at idle and when cruising at speed. Also shut off a couple of times at a stop. Seems to pull fine under throttle.
Backstory, this car sat for several years. All fluids were flushed before driving, plugs and wires replaced. As stated it ran fine for a while then developed issues the last couple of days.
I need this one dependable to use occasionally as a daily until I get the trans rebuilt in the '94. Gets better mileage than the F150.
Any ides where I may look next? I do have a scanner that will give live data if that would help me pinpoint the cause.

 

Until those with more experience chime in: I'm in a similar place with my '96, it has spent 99.9% of its time in a garage the last 15 years, and I bought it to drive it. So a few things to think about: Check fuel pressure. Going down the fuel pressure path might reveal if gas sitting in the tank, pump, lines, filter, rails, injectors, etc. has gummed anything up. Apparently ethanol-laced fuel sitting in these cars is not brilliant if they're not driven frequently. There's a procedure in the FSM, widely discussed here also. That appears to have been my main problem--leaky injectors, ran a little rough and had trouble with warm starts (not cold starts). I want to once-and-done this so I'm doing a full fuel system overhaul, doesn't cost that much. All this work is in process so the jury is still out.

I also had occasional idle problem, wanted to die, sounds a little like your issue--Based on a lot of reading here I think it was a bad idle air control valve. I took it out and cleaned it up, reinstalled it, but had the same problem again. Only happens sometimes, not all the time. So I just replaced it but don't have results yet, doing other work on the car. Might be dumb to do all this at once, instead of one thing at a time, but here we are.

I am confident these can become competent, reliable dailies. Good luck with yours!

 

Try disconnecting the vacuum line to the EGR, plug it, and then drive it to see if it acts up. The EGR might be sticking open. With 140K it could be worn.

 

I do suspect EGR. It had an EGR and ICM codes the first time I checked it.

 

Got a fuel pressure gauge. Idles at 42psi. Driving stays about the same. Hard throttle stays about the same. I did die idling twice in gear. Both times, pressure jumped for a second, then dropped back to 40 or so and held. Cleared codes before driving. Came back with IC 1372 4x (too few pulses) and EGR.I can open and close the EGR manually, seems to move without sticking. Maybe possible it isn't closing all the way?
Ideas on the too few pulses for ICM? It came off my '94 and had no CEL or running issues on that car.

 

Problem with the EGR, is if it's bad, it will stick when hot. It will seem OK when cold.

 

After sitting for an hour after shutting off fuel pressure gauge reads 26 psi.
Going to try cleaning out the EGR to see if the code for that will go away.
Any ides on the "weak pulse" issue?

 

After sitting for an hour after shutting off fuel pressure gauge reads 26 psi.
Going to try cleaning out the EGR to see if the code for that will go away.
Any ides on the "weak pulse" issue?