1990 S2 - stall when driving
 

The 1990 S2 is new to me. Yesterday, I had it parked all day in the commuter lot then went to drive home. So the engine was good and cold. In stop and go traffic, I let off the gas (was going maybe 20 mph) and applied brakes. The ! came on an the car stalled. Started just fine and drove a little futher (as in feet!) and the same thing happened.

I started it again and revved it up. No issues. But the idle would stumble a little bit. Got close to home ~5 miles and the car died once more.

It's been sitting ever since.

I have driven this car twice on the track since I got it. At one point it started and then stalled. Someone nearby said that it smelled rich when I re-started it. When starting it normally, I cannot tap the gas like I can with my 86 n/a or it won't start.

So, what might be the issue? I did a quick search and found all the following possibilities:
- Leaky injector?
- Fuel pressure regulator?
- Dirty TPS?
- Bad DME (BTW, is a n/a DME the same as an S2)
- Vaccuum leak?

Where to start? Thanks!

I have a lot of hands on time with the n/a, but not this S2. (SO far only changed the oil, brake pads and driven the snot out of it!)

Does the car idle always bad as you describe or idles OK and only sometime misbehaves.
I would look first at electrical issues, connectors, plug wires etc. Then look for any vacuum leaks.
Also does the car have good power?

One easy thing to check that was causing my S2 to stall is to disconnect and reconnect the plug to the airflow sensor. It's somewhat hidden underneath the sensor housing, but you just need to press on the plug retainer clip with your index finger for it to slip off. Clean the contacts and reconnect.

As for the rich smell, is it making black smoke? Check http://www.clarks-garage.com for how to test the fuel pressure regulator. When they go bad, they fail in "open" mode, flooding the car with fuel, which may be the reason for the car stalling.

Don't recall any usual misbehavior. I don't drive it a lot, but have only owned it 2 months. Power seems good. Well, compared to the 8v n/a. :)



No black smoke that I noticed. I'll have to test that. I'm out of town for a couple of days, but I'll check it out and report back.

The stalling was non-dramatic. The car is very quiet, if I hadn't looked at the dash I wouldn't have known it died.

Bad ISV?

I would start with the DME relay. It's cheap and easy to replace.
That kind of non-dramatic and sudden stalling is very typical of DME relay.

I put my S2 on the smoke tester here at the shop to test for vacuum leaks and I found that my throttle body is leaking, so I am putting together and throttle rebuild kit for it. I would see if you can get access to a smoke tester and try from there. Start there first as its and inexpeisve fix and takes about an hour to complete, including remocing and reinstalling the the thorttle body. Also as Wallace said replace the DME relay as well.

Good luck