Betty the Black E21 BMW 320i

[Senor_Taylor]

Since I bought the car, it idled at 1500 and it was way more annoying than you can think. I'm not making a joke when I saw I had to turn my car off at the starbucks drivethrough to order my coffee before cars and coffee (lots of jokes to be made there). I had been hunting vacuum leaks and found none and my last resort was perhaps the oil pan gasket leak causing a loss of vacuum. I was doing some late night forum browsing last night and saw one post where someone claimed their idle screw didn't turn as far as they thought it should. That seemed relevant to me because I had cranked on mine and it seemed bottomed out. I went outside this morning and unscrewed my idle screw to find all kinds of crud and corrosion coming out of the threads as the screw came out. Then I saw the o-ring fall out in two pieces.

Parts car to the rescue once again! I pulled the idle screw out of the parts car intake, inspected and cleaned it, then cleaned out the screw hole on my car and reinstalled everything. The screw rotates much more freely now and I was able to get the idle down to 800rpm with no issue!

Now that the idle was right, I was able to finally identify that exhaust rattle that annoyed me so much. When the idle dipped below 1000 rpm, the heat shield on the manifold would rattle around. I took it off and now I have a MUCH quieter and less shaky car!