CIS-Decel Question

[tutzilla]

I'm trying to trouble shoot a cold start idle problem (lack of increased idle at start). In the process of looking at how to remove my AAR to test, I noticed that my Decel valve has two hoses coming into it on the back side and no hose coming out of it on the other side. There is a nipple on the other side of the valve but no hose coming off of it. Maybe this is a dumb question but is this a problem and if so where does the missing hose go to? Thanks, Rob.

[Paulporsche]

You can usually find this kind of info in the exploded parts diagrams section of the tech area.

www.pelicanparts.com/911/911_Parts/1978-83/1-7-3.JPG

[radcon]

Are you sure you're looking at the decel valve and not the aux. air valve. What year is your car? I have an '80 SC with both the decel and aux air valves located on the passenger side of the engine. Both valves look alike but only the decel valve has a vacuum line attached to the small nipple.

[tutzilla]

Thanks Paul for the link! Radcon, I have an 81SC and I am almost sure it is the decel valve. It is located about 4 inchs to the right of the AAR. I believe AAV is in a much harder to access area. Thanks for the input.Rob

[vash]

tutzilla. so the nipple in the middle of the decel valve is left opened? on my 81 it is the same way. look around, you should be able to find the vac hose laying around with a plug in the end. i asked a mech buddy and he said they all do it. apparently, it is there as a smog requirement that allows the revs to drop fast (or slower, i cant remember). i think maybe slower. i put a vac cap on the nipple as well. it will not harm a thing. i plugged it back in, and i really didnt notice any diff. so i unplugged it again.

cliff