930 Idles high at startup hot or cold

[930Euro]

Hi this is my first post. My 1984 euro 930 idles high at startup. The only way to get the idle to normalize is to start driving. Once driven it idles normal. If I shut it off and restart, it idles high again. Any ideas on what is causing this? Thanks!

[john walker's workshop]

the auxilliary air regulators on 930s are overactive. get one from an SC.

[spuggy]

Welcome to the board!

Allow me to be the first to badger you for pictures. We like pictures!

I've never let any motor I care about idle when cold. Rich mixture, minimum oil flow - never seemed like a great idea. 911 owners manual even explicitly says not to do it, and to drive off immediately.

Like John says, the 930 AAR is especially obnoxious on a warm re-start (like if it's been off for 15-20 minutes or so), but the idle should drop back down to something reasonable pretty fast - like a few minutes sitting still, less if you're driving.

I've always regarded it as a hint that you just don't start the car until you're prepared.

[Paulporsche]

Would 911SCTarga's thread on AAR adjustment apply to 930s?

[930Euro]

Thank you all for quick reply. I will get pictures up shortly.

Will the SC AAR bolt right up or do I need to modify it? Does anyone have the correct PN of the AAR I should buy?

[JFairman]

The CIS and L-jetronic cold start aux air regulator valves are a compromise and the only way to get around it completely is remove it and install a 924 heater valve in place of it, it fits the hoses perfectly, and generic choke cable or early 911 heater diverter valve cable and lever to operate it manually.

If there is room above the flat intake manifold and below or behind the aircleaner like on a 930 you could leave the AAV where it is and use a longer hose from the back side of it to the intake manifold below the throttle body and install the 924/BMW 320i heater valve in that hose.
Part number: 944-572-085-02-M53
Pelican Parts - Product Information: 944-572-085-02-M53

The 924 version of the heater valve is alot lower priced than the 320i version and they are next to nothing in junk yards. Just install it so the air flow direction correlates to the little arrow on one of the hose connections.

I've done this before, it's very simple and works perfectly.
Leave the valve open and the AAV works the same as it always did.
The valve just allows you to manually adjust how much air is bypassing the throttle butterfly while the motor is cold or when the cylinders and heads are hot but the AAV is cold and making it idle annoyingly high until the 12 volt bimetallic spring heats up and closes the AAV.

[930Euro]

Thanks for the reply...will keep in mind as a last resort. I found a few other posts which describe how the AAR can be adjusted which seems to correct most of the same issues as mine.

[totle]

Check out the 930 forum. This has been discussed before and can give you some good info

Idle Screw Bottomed Out?

[9dreizig]

Where are you ?? **** can the air injection system if you don't live in CA. Also couldn't this be the WUR ?? Come on over to the 930 forum.. we're a freindly bunch

[T77911S]

something in the dizzy?

[930Euro]

Originally Posted by 9dreizig

Where are you ?? **** can the air injection system if you don't live in CA. Also couldn't this be the WUR ?? Come on over to the 930 forum.. we're a freindly bunch

I live in CA.