924T High Idle

[lyonsfin]

I recently purchased a 1982 924 Turbo. It recently received new timing belt and radiator upgrade to 944 style. Car starts fine, but it idles high, 1500 rpm. I tried adjusting the idle screw but it didn't do much. Any suggestions?

[Gawernator]

vacuum leak?

[924RACR]

The idle adjustment screw won't actually change the idle speed - that's managed by timing. So if it's that far off, yes, vacuum leak.

Have all the vacuum hoses and elbows already been replaced? There's a lot of 'em, including some rather-well-hidden ones...

[fiat22turbo]

Not too mention the throttle body itself, which can have shaft leaks and cause idle issues. Time to spray some water with a spray bottle on an idling engine to see if the throttle body, injector holes, vacuum lines/fitting or intake tubing is leaking.

Good luck!

[preludeofwrath]

have you tried cleaning out the TB with some carb cleaner? my old 944 had a gunky TB flange that contributed to crappy idle.

[lyonsfin]

Thanks guys. Great suggestions. I was thinking along these lines, but it is great to get some support.
Josh

[kcoyle]

Adjustment procedure below.

924Board.org :: View topic - Idle speed adj for '81-up 931 (+throttle stop set procedure)

Credit to 'Smoothie' and his great posts.

[ideola]

Throttle body reseal kit.

[924RACR]

I did just use the above TB reseal kit on my car (an 82), pretty straightforward... I know I did have leaks before, though I can't comment yet on performance after as I haven't driven the car since the rebuild...

The symptoms were very amusing, as the idle would be high sometimes but not others - mainly based on engine warm-up... don't remember if it was high when warm or when cold...