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2025 C3 ('68-'73) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2019 C3 of Year Finalist (stock)
Quadrajet choke stuck open
Hi guys, first off my Vette is running great but a few things have cropped up that I haven’t been able to work out so I’ll take them one at a time.
On cold starts the motor cranks and cranks like there was no spark or no gas. But with a few sprays of auto start I can get it running and once it’s warmed up it starts right up like a champ. The jets squirt gas when I pump it so I know it’s not a delivery issue and as it starts with a few sprays of either it fires up so it’s getting spark too.
Checking the choke I find the flap is stuck wide open. The linkage to the flap is getting stuck. I made a video of what’s going on so hopefully someone knows how to get this resolved. Please have a look at the video. 1971 350/270hp with original Quadrajet and has AC
We need to see the passenger side of your carb and intake manifold in detail. That’s where the choke assembly is.
I have the same year/engine as you do. There is a choke spring assembly that is on the manifold that connects to the carb with a small rod. The spring closes the choke when the motor is cold, and as the motor heats up, the spring unwinds and opens the choke. Sounds like yours is missing/disconnected/misadjusted.
Hello fellow vet head. Just for ***** and giggles after you get the car started and while it is running, spray some carb and choke cleaner down into the linkage tunnel while working the throttle as to not stall the engine. And just out of curiosity is that a heat, vac, or electric choke?
If you pump the throttle three times and it doesn't fire then the accel pump probably needs to be replaced......or you potentially have a weak spark or **** gas.....
You should be able to start it and keep at least running until it is warm.......
Yes the choke should work but I feel you have something else going on......
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2019 C3 of Year Finalist (stock)
Originally Posted by wwiiavfan
We need to see the passenger side of your carb and intake manifold in detail. That’s where the choke assembly is.
I have the same year/engine as you do. There is a choke spring assembly that is on the manifold that connects to the carb with a small rod. The spring closes the choke when the motor is cold, and as the motor heats up, the spring unwinds and opens the choke. Sounds like yours is missing/disconnected/misadjusted.
ok will make a new video with the air filter off and details of that area…
Do you still have the same carburetor that you posted in 2019?
Originally Posted by Daveinspain
I see you were missing the clip that goes on the choke thermostat spring rod, maybe the choke rod came out. I would check that all of the choke components are working and moving freely.
I sent my carb out to Lars the Quadrajet guru.
My car was running very rich. Among other things he found that the diaphragm in the choke pull off was punctured and inoperable. He fixed that and several other things and now the car runs like a champ.
Forgot to add that spring is pressed or staked to its mount. If it becomes loose, it can rotate as it warms up instead of pushing up on the choke. With that little sheet metal cover over the spring, everything can look perfectly hooked up, but the spring won’t actually be doing it’s job.
2025 C3 ('68-'73) of the Year Finalist - Unmodified
2023 C3 of the Year Finalist - Unmodified
2019 C3 of Year Finalist (stock)
Originally Posted by 71 Green 454
Do you still have the same carburetor that you posted in 2019?
I see you were missing the clip that goes on the choke thermostat spring rod, maybe the choke rod came out. I would check that all of the choke components are working and moving freely.
Choke closed
Choke open
Yeah I still have the same carburetor and I see what you mean about the missing clip. I never noticed that before. Thanks for posting the pics and pointing it out. I remember you mentioned that back in 2019 but I didn’t know where the clip was that you were talking about or what it looked like. The pics really helped..!!
Yeah I still have the same carburetor and I see what you mean about the missing clip. I never noticed that before. Thanks for posting the pics and pointing it out. I remember you mentioned that back in 2019 but I didn’t know where the clip was that you were talking about or what it looked like. The pics really helped..!!
Whenever I check my choke operation with engine cold, I remove the air cleaner, stand on the passenger side and reach over and operate the throttle to see if it closes properly. Start at the choke thermostat spring to see if it pulls down and go from there. Follow the choke linkage.
Quadrajet choke stuck open
