Random Stalling while braking!

Mr. '92 · #1 (**permalink**) 09-10-09, 05:20 PM

I decided to start a new thread since my hissing problem was fixed. My car randomly stalls while braking. I replaced my MAP sensor because the was an E31 code, and I thought it was fixed, but it's not. There is no pattern to it. I drove it for an hour the other day and it didn't do it. Then today, after no more than a minute of driving, it did it again. It starts right back up and there are no codes listed. When I first turn it on, it idles at 580-630, then after driving for a bit it idles at 600-650. It is a little shaky. Not sure if that has anything to do with it. The throttle body is clean where it opens up, but the tubes inside the TB look a little grungy. My car has so many random problems, I don't know what is related to what. Any help or ideas or leads will be GREATLY appreciated. Thanks!

**Ranger** · #2 (**permalink**) 09-10-09, 05:37 PM

"Grungy" EGR tubes are not a problem as long as they are open. Perhaps an intermittent ISC motor failure. Not sure how you would test that without throwing an expensive part at it.

Mr. '92 · #3 (**permalink**) 09-10-09, 05:52 PM

Quote:

Originally Posted by Ranger

"Grungy" EGR tubes are not a problem as long as they are open. Perhaps an intermittent ISC motor failure. Not sure how you would test that without throwing an expensive part at it.

Thanks Ranger. If the ISC motor was going bad, would that explain both the rough idling and the random stalling?

**Ranger** · #4 (**permalink**) 09-10-09, 06:02 PM

It could cause a stall for sure. I suppose the idle could get rough if it dropped low enough. Otherwise I don't think I'd suspect the ISC motor of a rough idle.

cadillac_al · #5 (**permalink**) 09-11-09, 12:40 AM

The ISC is supposed to raise the idle when the brakes are applied. Do you have the owners manual? You could try the idle relearn process or maybe the ISC isn't working at all.

Slipgate · #6 (**permalink**) 09-11-09, 02:21 PM

The brakes work on engine vaccum. A vaccum leak in that line is perhaps robbing your engine of too much vaccum causing it to stall. Do your brakes work fine?

Mr. '92 · #7 (**permalink**) 09-14-09, 12:36 AM

Sorry it took so long to respond. Busy with work and school. Anyway, my brakes work the same as they always have. If it helps any, when it stalls, the oil and charge lights come on. Recently though, I almost stalled. The oil light came on and it felt like it was going to stall, but this time it revved back up and the oil light disapeared and the charge light didn't come on. It was fine after that. Does that narrow down the problem any?

**Ranger** · #8 (**permalink**) 09-14-09, 12:45 AM

No. Oil pressure and charge light always come on when it stalls. That's normal. Same as turning the key on, but not starting the engine.

cadillac_al · #9 (**permalink**) 09-15-09, 08:14 AM

Your ISC needs to be adjusted or replaced. This site is a wealth of information and there are hundreds of posts here on the ISC. It's a simple fix but most auto shops probably haven't dealt with them in years so you are better off to research it yourself than to pay somebody to learn on yours.