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Old Jul 1, 2019 | 07:13 PM
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Default Running rough

I had just rebuilt the carb and it’s acting the same as it did before I had rebuilt it, it would idle kinda high at 1000 then after a little drop down to 750 then I’d drive it and I’d put it in neutral or it will shut off(might be cause the big can I put in), but then if I floor it it would stick at 2000 and then it would just want to shut off after that, anyone have any thoughts?
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Old Jul 2, 2019 | 05:35 AM
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vacuum leak, choke issue or linkage issue. Have you checked your timing as well. what are you set at?
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Old Jul 2, 2019 | 07:23 PM
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I can’t remember what we set timing at but timing is good, I haven’t put any of the vacuum lines back I just plugged the 3 (not the distributor or brake booster vacuum lines), what do u mean by linkages? And I had my auto teacher set the timing and set the choke, but I feel like the choke might be the culprit but I’m not sure how to set it
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Old Jul 3, 2019 | 03:19 PM
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Contact Lars here on the sight. He only uses email, no messeages. There are some threads showing the linkage and how it should look if yo do a search. It sounds like your idles are set too low. My high idles is atleast 1500 rpm, then it kicks down to 1000 or so, once its warm it will drop again to 750 where its set. If your shop teacher set the timing to factory specs then its too low. That would be factory emmissions specs which really hurt the horsepower numbers. Ask Lars or his timing papers, as well as his carb papers. I'm guessing you have a factory Quadrajet, what extactly is your carb. Can you post pics as well

Lars email
V8FastCars@msn.com

Last edited by Rescue Rogers; Jul 3, 2019 at 03:20 PM.
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Old Jul 3, 2019 | 04:27 PM
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I agree that the idle is to low but why would the car get stuck at 2000 rpm?
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Old Jul 3, 2019 | 04:34 PM
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Sticking throttle cable?
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Old Jul 3, 2019 | 04:36 PM
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No it’s not that cause it would only happen when the car is warm, and I tried to see if that was the case but everything was fine
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Old Jul 3, 2019 | 05:02 PM
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Originally Posted by gabesaad10
I agree that the idle is to low but why would the car get stuck at 2000 rpm?
A binding in the secondary throttle shaft?
A throttle blade hung-up on the carb base gasket?
A binding in the link between primary & secondary shafts?
A weak or incorrectly installed throttle shaft "spring"?
A throttle return spring hooked in the wrong location?
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Old Jul 3, 2019 | 05:10 PM
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what year is the car?
what engine is in the car?
what carburetor is on the car?
can you post a picture/s of the carburetor and the connections to it?
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Old Jul 3, 2019 | 05:45 PM
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Choke.
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Old Jul 3, 2019 | 05:50 PM
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Originally Posted by MelWff
what year is the car?
what engine is in the car?
what carburetor is on the car?
can you post a picture/s of the carburetor and the connections to it?
It’s a 1977 it has a 4 barrel Rochester
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Old Jul 3, 2019 | 05:50 PM
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Originally Posted by JBrooke825
Choke.
What should I do to remedy it?
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Old Jul 4, 2019 | 07:21 AM
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You would be better off talking to Lars. Mine is a 69. He will have the answers for you.
good luck.with your problem.
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Old Jul 4, 2019 | 11:34 AM
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Originally Posted by JBrooke825
You would be better off talking to Lars. Mine is a 69. He will have the answers for you.
good luck.with your problem.
Wait who is Lars?
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