2000 BMW 323i - stalling

bmw
323

#1

I have a year 2000 BMW 323i with 125K on it and automatic transmition. It stalls quite often when I’m coming to a stop at a light or stop sign. Right before a complete stop, the engine just shuts off. It starts right back up after that, and it’s not a battery problem (according to my mechanic). Any thoughts?


#2

First 2 thoughts: 1) leak in the brake booster - opens up a sudden, massive vacuum leak. You can learn about this pretty easily with a vacuum gauge. 2) an idle air control (IAC) valve that is getting sticky and not opening up fast enough. These can be tested and cleaned.

But its hard to say since you don’t really say much about the car otherwise.


#3

There is/was a common problem with this car that should have been fixed under a recall. There is a fairly large vacuum hose under the upper valve cover that tends to degrade and leak vacuum. We replaced many, many, of these hoses under the recall, perhaps your car was missed, or the hose has still degraded. An exploded view of the vacuum hose routing will show this hose. It is a little tricky to get one end to release (this is a proprietary hose, generic hose will not work due to the special ends).