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T77911S T77911S is offline
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Join Date: Oct 2006
Location: MYR S.C.
Posts: 13,546
the way you worded it has some confused as to if the CIS is from the 75 or 87.

assuming it is the 87 CIS, was the ECU/electronics installed for the 87? O2 sensor?

sounds like he replaced the aux air regulator (AAR). all it does it let more air into the engine when it is cold, then it closes to bring the idle back down.
the first thing i would look at is the AAR. he may have replaced it but it could be stuck closed or stuck open and the PO adjusted the idle to compensate.
check for power at the plug going to the AAR. remove it and look for 12v across the 2 pins, with the key on.

the warm up regulator(WUR) could also be bad. mixture and/or control pressures could be set for when it is warm compensating for a bad WUR. that would make it run good hot and bad cold. you need fuel pressure gauges to check pressures.

check for air leaks.
86 930 42kmiles [__] RUNNING:[__] NOT RUNNING: ____77 911S widebody: SOLD
88 BMW 325is 200K+ SOLD
05 BMW 330CI 130K:: [__] RUNNING: [__] NOT RUNNING:
08 VOLVO V70 190K:: [__] RUNNING: [__] NOT RUNNING:
Old 10-30-2014, 08:54 AM
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