It looks like my idle air motor for my wagon is dead. My '84 245 has had a high idle since I bought it a year ago, in the neighborhood of 1K rpms. I just replaced the wiring harness, so that factor is out. When the car is idling, I can feel no vibration or humming from the idle motor. The Bentley book says this is a wiring fault or a dead motor. Now, my question is two-fold. First, should I fix/replace the idle motor or should I just not worry about it? There is a little lurch going into gear (auto trans), but it is not extreme. Second, which idle motor should I have? 501 or 520? The tag on mine has been wiped off and all that is still visable is the name "Bosch", but no number. Is there any way of telling without the number or any other markings on the idle motor that might give me a clue?
Thanks,
Nick