High Idle Testing - Interesting observation

[86 911]

My car has had a high idle lately. I've replaced the WUR and AAR so far, but both of those parts didn't help at all. Today I took the airbox cover off and put my hand back where that float device is. I have no clue what it's called, but it's that metal thing that regulates how much air is allowed through the airbox. So, I started the car, and sure enough it idled over 2K RPM. Next, I lifted down on that float-like device and the idle came down to 1000 RPM. Just a tad lower would cause the car to die. Note: I only had to push down on the "float" very little for the idle to significantly drop. As I am doing this, the car is running very rough and shaking. What's going on? Could that "float" need to be adjusted lower to reduce my idle?


Note: The car still idles high even with the idle screw all the way in.

[BeauBlues]

Matt that thing you are playing around with is the MAF. It does not reguate air, it measures it. My guess is that your high idle is not due to the MAF. If you have waynes book it tells you how to adjust idle speeds. Also you should check your accelerator linkage. I had to adjust mine to get my idle right. These are just a few things you should check before you start buying parts.

[Wil Ferch]

I'm unclear what car you have...your "name" says 86....the text says pre-84 ( CIS type car... like an SC).

???

Wil

[86 911]

Thank you BeauBlues and Wil Ferch. Wil, my car is actually a '76 with a '78 SC Euro engine. My username can be tricky . I'm pretty sure I have a vaccum leak somewhere, so I'll just host an "engine drop party" soon and find the trouble .