: Low speed stall



jerry23
04-06-09, 09:02 PM
I really need some help. My 99 Seville SLS stalls at low speeds, I drive
58 miles to and from work with no issues until I slow down for traffic jam or to get off at my exits. This only happens when I get to a very low speed and not always. I have had the TCC solenoid replaced because I was told that was it. It was OK through the winter, but now that its warming up a bit, it stalls regularly at low speeds. The only code I can get from the display is a 1599 code (stall condition):confused:

Ranger
04-06-09, 09:54 PM
Try cleaning the TB and the EGR valve, even though the EGR should set a code if it was sticking open.

jerry23
04-06-09, 10:49 PM
Thanks Ranger, I tried both of those things. The throttle body was all gummed up and the EGR was clean. I have read many posts and thought about replacing the Crank Position Sensors even though I don't get any related codes. Do you think that might be it?

Ranger
04-06-09, 11:02 PM
CKP sensors do not always set a DTC. '99's where not part of the bad batch, but your symptoms do match. It would be a shot in the dark.

jerry23
04-06-09, 11:09 PM
I'll give it a shot and let you know if it helps. If anyone has any other ideas I would appreciate it. This is very frustrating and dangerous.

jerry23
04-21-09, 07:31 PM
I haven't replaced the CKP sensors yet but I did remove the IAC valve to look at it and it was full of carbon deposits. It idles smoother now and has not stalled until today. I got off at an exit going from 70 down to around 35 slowly. I noticed at one point while slowing down the tach suddenly dropped until I gave it gas and it recovered before stalling. Could this be related to the speed sensor on top of the tranny? Ranger or Sub are you out there?:confused:

Ranger
04-21-09, 08:18 PM
That would be the VSS. Not sure what happens when that fails, but it should set a DTC.

jerry23
04-21-09, 09:03 PM
Ranger no codes have been set. This is becoming a dangerous situation. Any other thoughts?

Ranger
04-21-09, 09:56 PM
Other than wild guesses, I'm out of ideas.

2009chopper
04-24-09, 11:56 PM
i think ranger is right....i had the same thing happen on my 2000 dts. i would pull up to a light and it would stall, took it in and it was the crank sensor. they replaced it and it worked great after that.

Ranger
04-25-09, 10:40 PM
A TCC clutch not disengaging would stall the engine as well. Just like trying to stop a standard transmission car without stepping on the clutch. That said, it should set a DTC (P0742 I think).