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Old 10-03-2015   #21
RussMcB
 
Join Date: Jan 2015
Location: Marietta, GA USA
Posts: 1,160
Default Re: Very High Idle

I enjoyed having a nice low idle for a couple of minutes, but it was back high again by the first stop light.

When I got back home I did the phone book trick to stop the air going into the front snout and my idle stayed high. So, sure enough, I do have a large vacuum leak problem.

With the car running and the snout still blocked, I pulled and plugged all the easy-to-reach vacuum hoses one at a time. I could hear slight changes in RPM but none of them brought the idle down when it should be. I think that means my large leak may be under the plenum.

Today I'll repeat those tests, and try a few more things with the plenum in place, then pull it if I haven't found the leak yet.

I'm wondering if, since the idle was nice and low for a few minutes, maybe the leak is related to a source that is being controlled by the car.

Saturday afternoon update:
I blocked off the front snout, ran the car at idle, sprayed some carb cleaner under the plenum (front area) and the idle went up. So, I'm taking off the plenum now, expecting/hoping to find an obvious problem.

Last edited by RussMcB; 10-03-2015 at 05:50 PM. Reason: Added Saturday update.
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Old 10-07-2015   #22
8cam
 
Join Date: Jul 2013
Location: Atlanta
Posts: 451
Default Re: Very High Idle

Hey Russ, did you find it? I had a similar problem that turned out to be a vacuum hose I forgot to reconnect...self-inflicted. 2k idle and would not come down. I still have a small leak somewhere, but nothing like it was. I need to pull my plenum again and run it down.
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Old 10-07-2015   #23
RussMcB
 
Join Date: Jan 2015
Location: Marietta, GA USA
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Default Re: Very High Idle

Yes, my issue was very much like yours. Tonight I'll be rerouting all vacuum lines from underneath the plenum to above (it should be relatively easy on my car since I don't need vacuum for secondaries or evap). If things go smoothly I'll take it for a test drive before bedtime to see if it's all good. Hope so, because I'm leaving Friday for Tony's C4 BBQ Gathering, and taking it to a Road Atlanta track day the next Friday. I'll probably squeeze in another trip to the dyno, to check my air/fuel ratio. Busy days.
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Old 10-08-2015   #24
8cam
 
Join Date: Jul 2013
Location: Atlanta
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Default Re: Very High Idle

Who's the track day with? And do they allow spectators? I'd love to get up there and just enjoy the day. Petit LeMans was a waterlogged mess, but I still had fun.
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Old 10-08-2015   #25
RussMcB
 
Join Date: Jan 2015
Location: Marietta, GA USA
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Default Re: Very High Idle

Quote:
Originally Posted by 8cam View Post
Who's the track day with? And do they allow spectators? I'd love to get up there and just enjoy the day. Petit LeMans was a waterlogged mess, but I still had fun.
These guys: http://www.jzillatrackdays.com

I've done several events with them (mostly at AMP). Always fun. Pretty laid back. Yes, they'll allow spectators. If you're free you should come. Bring a helmet. There will be plenty of folks who'll let you ride along.

Petit LeMans was fun to watch on the web. I'll bet it was fun to be there in person, even with the soggy weather. Pretty interesting that a non-prototype won overall.

I might have fixed my high idle, but gave myself a new problem - no start. Heading back to the garage to troubleshoot that...

On edit: Yes, my high idle seems to be gone (based on my 20 second test after getting it back together). It sure sounds nice(r) when the idle is where it's supposed to be.

My problem was probably one of the large evap hard lines not staying in place.

Last edited by RussMcB; 10-08-2015 at 09:33 PM.
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Old 10-09-2015   #26
8cam
 
Join Date: Jul 2013
Location: Atlanta
Posts: 451
Default Re: Very High Idle

Quote:
Originally Posted by RussMcB View Post
These guys: http://www.jzillatrackdays.com

I've done several events with them (mostly at AMP). Always fun. Pretty laid back. Yes, they'll allow spectators. If you're free you should come. Bring a helmet. There will be plenty of folks who'll let you ride along.

Petit LeMans was fun to watch on the web. I'll bet it was fun to be there in person, even with the soggy weather. Pretty interesting that a non-prototype won overall.

I might have fixed my high idle, but gave myself a new problem - no start. Heading back to the garage to troubleshoot that...

On edit: Yes, my high idle seems to be gone (based on my 20 second test after getting it back together). It sure sounds nice(r) when the idle is where it's supposed to be.

My problem was probably one of the large evap hard lines not staying in place.
Hmmm...looks like the RA event is still open, wonder if I can get in? Been a while since I've been on track and this would be a blast. Petit was a great race and the rain was a hell of an equalizer. The GTLM Porsches were outlapping the prototypes for most of the race, really awesome to watch. We had an ezup in turn 5 so we didn't get too bad, but the mud was epic.
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Old 10-11-2015   #27
8cam
 
Join Date: Jul 2013
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Default Re: Very High Idle

Event was still open, I'm in! Will be great to be back on the track again!
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'90 ZR-1 #1322 Daily Driver, 64k and counting
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Old 10-11-2015   #28
RussMcB
 
Join Date: Jan 2015
Location: Marietta, GA USA
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Default Re: Very High Idle

We're going to have a blast. My car ran great all weekend (trip to Tony's barbecue in Alabama). It is SO nice (low idle, lots of power, great new sound). We'll install racing brake pads, bleed 'em and we'll be all set.

And, since you were at Petit LeMans last week, you saw what we need to do to go fast there, right? :-)
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Old 10-12-2015   #29
Gunny
 
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Default Re: Very High Idle

looking forward to hearing the new sound ... maybe a quick ride around the block, or better still, a run through the mountains
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