<![CDATA[m42 ICV question]]>Question for the m42 folks. I've noticed that the ICV in my 1991 318is is quiet when I turn the key and when the car is running. No buzz/hum that I can feel or hear unless I use a mechanic's stethoscope and even then I can barely hear it. In comparison, the m20 ICV in the 1990 325i hums like an angry hornet when I turn the key. I found one post that said the VDO ICVs are quiet while the Bosch ones hum? I haven't checked to see which brand is on the car. ICV has been cleaned and ohms out correctly. Anyone else with a m42 care to weigh in on what is normal?

Part of the reason for asking is that I still have a slight idle stumble that I'm trying to track down. Needle stays around 850 but seems like it misses at times. Only at idle. No miss/stumble under load. Vacuum hoses all replaced, new intake boot, plugs and wires replaced, oil filter housing gasket and o ring replaced and oil dipstick tube o-ring replaced (to solve some oil leak issues), coils ohm out correctly, sensors ohm out correctly (temp, CPS, etc). Could be intake manifold gaskets which I haven't replaced.

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