QuestionQUESTION: 1989 325is Vin#WBAA2300KEC49414
Don, when the car is idling or periodically when it is underway it idles to 1,000r.p.m and then surge back and fourth from 600-1,000r.p.m. the throttle cable plastic clip is inserted in its mount(I am not familiar with what the cable at this end should look like) and at idle there is about 1"-2" of free play(lose)at this end of the cable. I have ordered another cable assembly, but am not sure if this is the problem. any help on this would be greatly appreciated. thank you.
John
ANSWER: Check the idle control valve and the throttle plate to make sure they are clean and the adjustment of the plate is about .002.If the clean the valve doesn't help you may have to replace it as well as the idle control unit which is in the glove box
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QUESTION: Don, thank you very much for your quick response.
I checked the throttle plate, it fully opened closed smoothly(no noticeable gap).It was quite dirty,cleaned it with carb cleaner.When I started it up it idled smoothly about 600 rpm. It ran well on the test drive, when I put it in park went back to surging 1500-2000rpm(that is the same as earlier,600-1000rpm was a mistake). My check on the 3-wire Idle control valve(engine compartment)was: resistance on unit 39ohms on two outer terminals.Center to outside terminals 20&19ohms. Volts 3-wire harness plug center 12.12V outside 8.09V and 0.60V.what do you think.
John
AnswerYou need to clean the idle control valve as well.If there are any oil leaks front oil seal,oil pan gasket,valve cover gasket they need to be replaced because this is probably the cause of the throttle plate being dirty.Did you measure the plate? If you made any adjustments the throttle switch may need adjusting.What you need to is to check valve adjustment,plugs,dist.cap and rotor.The basics need to be looked at before any big changes are done.Oil leaks are a MUST to be repaired they are causing the most grief.It is an unmeasured air leak.
