AAR question
 

Hi, just a quick question.

When the Aar heats up and closes off should it be 100% air tight or should I be able to blow some air trough it if i try?

Go here http://forums.pelicanparts.com/911-930-turbo-super-charging-forum/674652-idle-high-2.html and look at post #28 for an explanation and picture of the AAR when mostly open.

Thanks for the reply,

My aar is apperently working ok. Opening when cold and closed when applied 12v( no light trough) but i’m able to blow some air trough with my mouth if i try. I'm just wondering if that is ok or if it should be 100% tight? I'm struggling with some intermittent high rpm at idle when warm, and when i took the aar out of the equation that problem went away. but of course now it diesat idle when cold if i don't manually keep the rpm around 900rpm

They are not air tight. Different engine type numbers use different AAR's, some of them have bleed holes as part of idle control. Typically when the AAR starts getting sticky it will either not shut all the way (high idle) or stick closed (low cold idle) or stick open (really high idle) depending on what caused the failure.

Ok, thank you. Then i believe i can give my aar a clean bill of health.

It is just a close fitting slide type mechanism. Against the vacuum of the engine it won't be totally airtight. But it should be fully closed when warm, and operate consistently between cold/warm. If it does those things, it is working as it is supposed to. The small amount of air that creeps past (your torch light) just becomes part of the idle bleed air mix. Your erratic warm idle may be an idle mixture issue (lean?).
Alan

Idle AFR is if i remember right around 12-12.5 at cold idle. (car is in winter hibernation now so can't check) Any how i believe my afr's are under control, but will of course verify when spring comes.i have a few other things I'm going to check what might cause this.

1: I believe my Ignition curve is to much advanced below 2000rpm I had it changed to a programmable msd 6AL-2 and i noticed it jumps right from retard to full advanced at 1050rpm. this seems wrong compared to the information i find about the curve. I plan to change this so it's not reaching full advance before 2000rpm

2: 1: electrical connection to AAR, is it stable.