LS Shuts off..HELP!

[LS_Summer]

I have a 2001 LS V8 and recently I have had problems with the engine shutting off while I am driving. Everything locks up, the brakes, steering wheel, everything just won't work. It starts right back up, but it happens a lot. Everytime I take it to the dealership it works fine and they cannot find anything wrong. Does anyone have any ideas of what could be going wrong?

[shorod]

Welcome to the forum!

We need you to clarify "locks up." When the engine dies, you'll lose your power assist to the brakes and steering. This will make it difficult to steer the car and the brakes will be less effective. However, this should not cause them to "lock up" which would indicate (at least to me) that the brakes are applied fully (locking up the wheels) and the steering lock engages, making it impossible to turn the steering wheel.

Also, are there any commonalities associated with the engine stalling, such as exiting a turn and stepping on the throttle, coming to a stop, when the temperature is below a certain temperature, after a rain, or after a stretch of highway driving?

-Rod

[LS_Summer]

The steering wheel will not turn and the brakes will not work when the engine dies. It happens at random times, not in any specific weather or conditions. It has happened turning and going straight foward. I just had a new alternator put on this summer as well as a thermostat and the resivoir had a crack and I had that repaired.

[shorod]

Okay, is SOUNDS like you are just experiencing the lack of power assist with the brakes and steering rather than a "lock up" condition. That is completely normal (well, the lack of power assist, but not the stalling).

Do you by chance have the temperature controls set to "Auto" when the stalling occurs?

You might be experiencing a faulty Idle Air Control (IAC) servo. The IAC should increase the engine speed under certain loads such as when the air conditioning is engaged, the steering is turned to one of the locks, etc. When the climate control is in "Auto" mode, the A/C compressor will cycle on and off to help maintain the set temperature. Maybe the IAC is not compensating when the A/C compressor engages and stalls the engine.

-Rod

[Quik_LS]

There was also a 'common-ish' problem that caused random stalling that was corrected by a PCM code upgrade. The typical issue showed up usually right as the driver was crusing and then lifted off the gas completely.

Caused a few 'tense' momments when autocrossing....

[LS_Summer]

I took it to the dealership one more time. They found the problem. It was the ignition coils. They were also causing several other problems just not as crucial as the shutting off engine. But thanks to everyone that tried to help me figure out the problem!