Stalling - P1638, P1639 Throttle Valve Position Control

[dellop]

Over about the last month, my car will randomly stall when completely warm usually when starting from idle. It has only happened about 3 times.

Then today, it did the same thing, except this time, it didnt quit, but idled up and down between 400-500 RPM. Luckely I had my code reader handy and read: P1638, P1639 - Throttle Valve Position Control -Throttle Stuck Permanently, Temporarily. Now these codes were pending and erased as soon as I started the car the second time.

Any suggestions as far as what to do? I have a 1000+ mile trip scheduled at the end of this week and am looking for some ideas.

Thanks
2001 325xi Sedan

[325isBaby]

Sounds like your Throttle is sticking, check to make sure it's not gunked up and the drive cables are in good condition...check it's range of motion both manually and electrically (have key turned on by friend and watch it run it's cycle) Good luck and keep us posted

[dellop]

Reading through the Bentley Manual, it seems fairly easy, but I am having trouble getting to the 2 hose clamps next to the throttle on the air intake. Any thoughts?

[dellop]

After doing some more research, here is some more information:
Previously I was getting an Intake Camshaft Position Sensor malfunction. I just replaced that this last weekend. Is it possible the camshaft sensor was the problem previously with the car stalling, and this last time, where I got the codes, was just a random occurance?

[Hootie]

A faulty position sensor will DEFINITELY cause stalling. If you think it was random, clear the codes and see if they come back (or if stalling continues).

[325isBaby]

Most definatly! Clear codes and see what comes back (or doesn't)