Idling high?
Thread Starter
Pro
Joined: Apr 2007
Posts: 736
Likes: 1
From: Chester VA
Idling high?
Having an issue getting my car to idle correctly. I can turn out the idle screw all the way and it'll idle at 1100 at 14* timing and no advance hooked up. Can't even begin to hook up the vac advance, it goes up even more. At the moment I have the timing at about 4* (estimated), I timed it to the desired idle rpm and didn't use a light. It's a new street avenger 670 on a mild 350.
Could this be a vacuum leak? I've checked over the system but haven't found one, although I'm still planning on plugging all vacuum lines from the motor to rule out a possible leak somewhere in the lights etc. My brake pedal is very weak (still brakes very well just no pedal feedback), could there be a vac leak in the booster, I've ruled out a leak in the line?
Could this be a vacuum leak? I've checked over the system but haven't found one, although I'm still planning on plugging all vacuum lines from the motor to rule out a possible leak somewhere in the lights etc. My brake pedal is very weak (still brakes very well just no pedal feedback), could there be a vac leak in the booster, I've ruled out a leak in the line?
Tech Contributor
Joined: Aug 1999
Posts: 14,373
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From: At my Bar drinking and wrenching in Lafayette Colorado
Disconnect the throttle cable to make sure the throttle is fully closing. If the throttle is closing, check the secondary idle speed screw to make sure it's not set high. If both primary and secondary throttles are fully closed, you have to have a vacuum leak in order for the idle to be high.
Lars
Lars
Racer
Joined: Apr 2007
Posts: 361
Likes: 0
From: Sacramento (Citrus Heights) California
If you've got a power assisted brake M/C, then yes it could. Try plugging the manifold tap for the brake assist and see if that helps any. If it does, you've likely got a leaky hose or a blown diaphragm in the brake assist.
Thread Starter
Pro
Joined: Apr 2007
Posts: 736
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From: Chester VA
Thanks fellas. It was a vacuum leak afterall. I was at a loss then decided to pull off the vacuum plugs, one that I've checked a couple of times looked great, but I blew through it and sure enough it had a big split in it. Also, the car has a full hood now which did away with the vacuum wiper cowl, discovered the previous owner thought a BIC ink pen was a good way to plug one of the no longer user vacuum lines. Idling great at 16* and vacuum advance now hooked up. I added an RPM intake, MSD dist and box, and a 670 street avenger several weeks back, now that I can run more than 4* of timing I'm finally seeing the benefits, car is much more responsive and power is noticably up. I think the brake issue is a failing MC and turned out not to be related, thanks for all the help.
Last edited by wiseman79; Nov 7, 2007 at 05:05 PM.
