CIS rebuild
 

So I've got crappy surging idle in my 76 911S that started after warm winter storage. Went out today and removed the oil filler cap with the car idling (roughly) and there was zero change in the idle which tells me I've got a vacuum leak, and probably a good one.
At this point would you guys recommend pressure testing to locate leaks, or would it be more prudent to pull the entire CIS system out and inspect/repair it on the bench?


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Removing the cap on a 2.7 doesn't change the idle because the oil tank is not a vacuum can like the SC/ Carrera. The hose to the air box from the tank vents the tank.
Bruce

Ahh; good point.


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Woo hoo; fixed my problem and the car is running like a dream again!
Took off the heater hoses, heater motor and bracket to get some room to see what was going on around the throttle body. I found a vacuum like be that had pulled off and was hanging down deep behind the engine. With the help of a mechanics mirror I was able the o see the port at the back base of the throttle body where it was supposed to go.
Popped her back on and she's growling like a lion again!


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