Off idle wierdness
Thread Starter
Pro
Joined: Aug 2001
Posts: 605
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From: hamilton square NJ
Off idle wierdness
What does this mean...I start up my car over my girlfriends and it's at like 180deg from being run already. I give it some gas and it almost stalls out but then comes back. Give it some more and it almost dies again. Then after about a minute the idle moves about 300-400rpm up and it's idleing normal, except for the same almost die thing. but after the car rev's over 1500 it's fine and revs normal.
Burning Brakes
Joined: Mar 2001
Posts: 1,211
Likes: 5
From: Nashville TN
Re: Off idle wierdness (ddn)
Sounds like vapor locck or the fuel was boiling in the carb. I had problems with a Holley that would do that. Stop the car for 10 minutes. Go re fire it and you would have to rev the p*ss out of it to get fresh liquid fuel into the carb before pulling out into traffic, other wise it would stuble or stall. Something that you didn't want pulling out into traffic.
Thread Starter
Pro
Joined: Aug 2001
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From: hamilton square NJ
Re: Off idle wierdness (dman535)
How do I fix a vapor lock problem with the carb? I'd have to say that the engine is running at 205deg in normal driving. It never runs 180 like it should.
[Modified by xfactor974, 6:36 PM 3/11/2002]
[Modified by xfactor974, 6:36 PM 3/11/2002]
Thread Starter
Pro
Joined: Aug 2001
Posts: 605
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From: hamilton square NJ
Re: Off idle wierdness (ksems)
If this were vapor lock, it wouldn't occur when I just start up the car right? It seems to be doing the same thing after I start the car, but get's progressivley worse but never stalls or anything.
Drifting
Joined: Aug 1999
Posts: 1,468
Likes: 1
From: Kirkland WA
Re: Off idle wierdness (xfactor974)
Have you looked at your choke? If you have the choke incorrectly adjusted it could close again even after warmed up and cause your car to stumble because it's being starved for air. Would be worse when the car is hot, and also not run right when cold.
I've found it's easier to rule out the simple stuff. Good luck!
I've found it's easier to rule out the simple stuff. Good luck!
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Melting Slicks
Joined: Nov 2000
Posts: 2,663
Likes: 3
From: Palm Harbor FL
Re: Off idle wierdness (xfactor974)
I'm not sure about the Demon carb, but there was an article on adjusting idle mixture in a Chevy High Performance a few months back and I think they did mention Demon Carbs in it. I'll look for it and scan it in for you. For some reason, I'm thinking you have 4 idle mixture screws, two on each side (my Edelbrock has two on the front). You have to go through a process of attaching a vaccum gauge to manifold vaccum on the carb and adjusting each screw to the point of maximum vaccum. That's the simplified version of it. I'll look for it and try to scan it in for you tonight if you'd like me to send you the article. However, stumbling just off idle is a symptom of idle mixture being off.
Thread Starter
Pro
Joined: Aug 2001
Posts: 605
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From: hamilton square NJ
Re: Off idle wierdness (79MakoL82)
79MakoL82 I have four corner idle. So I have an idle adjust screw for each corner. My email is xfactor973@hotmail.com if you would rather email it instead
[Modified by xfactor974, 9:37 PM 3/12/2002]
[Modified by xfactor974, 9:37 PM 3/12/2002]
Safety Car
Joined: Jan 2000
Posts: 4,143
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Re: Off idle wierdness (xfactor974)
Just a thought, but you might have a vacuum leak somewhere.
My 'ole '68 Camaro did that and the idle would change <vary>
....if you revved it - everything went away.
So as long as you kept it at 1500 or better it wouldn't 'die' or try to.
Although your fuel mixture sounds like it's on the 'rich' side....
IF you have 2 or 3 of these problems mentioned above, troubleshooting can be quite difficult.... never messed with that type of carb. so can't help there. :eek:
My 'ole '68 Camaro did that and the idle would change <vary>
....if you revved it - everything went away.
So as long as you kept it at 1500 or better it wouldn't 'die' or try to.
Although your fuel mixture sounds like it's on the 'rich' side....
IF you have 2 or 3 of these problems mentioned above, troubleshooting can be quite difficult.... never messed with that type of carb. so can't help there. :eek:
