Won’t run right
Thread Starter
6th Gear
Joined: Feb 2024
Posts: 6
Likes: 0
Won’t run right
Hey all, so I got my Vette street legal and I took her out for a ride yesterday around town. I noticed a few things: she wouldn’t go above 60, rough idle (carb tuning) but would also stop completely if I sat still for too long, needing me to start the car again. Just this morning, I went outside to tune the carb and hopefully fix the rough idle but the same issue happened, she’d just turn off. Any reason why this is happening? Battery is fully charged and I just installed a nee alternator a few days ago. Could this be a fuel line issue?
Thanks in advance
Thanks in advance
Is my vette stock?? HAHA
Joined: Oct 2015
Posts: 20,209
Likes: 9,348
From: Im not allowed to tell you
2020 C3 of the Year Finalist - Modified
2020 Corvette of the Year Finalist (performance mods)
2019 C3 of Year Winner (performance mods)
2016 C3 of Year Finalist
I bet you tuned it for the factory timing...Set your timing to 14 to 16 degrees BTDC and it will run better. Then do search for Lars Timing Papers. They are very informative and you will be surprised how much power you will unlock from your car. So what was not street legal about your car? Are you in CA or something?
IF thats not the case do you have the vacuum advance on a ported and not manifold vacuum port...thats usually number 2 on the list as well as a vacuum leak
IF thats not the case do you have the vacuum advance on a ported and not manifold vacuum port...thats usually number 2 on the list as well as a vacuum leak
1967 Pedal Car Champion
Joined: Mar 2020
Posts: 9,135
Likes: 4,244
From: US-PNW
Hey all, so I got my Vette street legal and I took her out for a ride yesterday around town. I noticed a few things: she wouldn’t go above 60, rough idle (carb tuning) but would also stop completely if I sat still for too long, needing me to start the car again. Just this morning, I went outside to tune the carb and hopefully fix the rough idle but the same issue happened, she’d just turn off. Any reason why this is happening? Battery is fully charged and I just installed a nee alternator a few days ago. Could this be a fuel line issue?
Thanks in advance
Thanks in advance
- What year is your car?
- What engine, carb, & ignition?
- How stock or modified is it?
- What kind of refresh has been done recently to the fuel delivery, carb, & ignition?
- What sort of experience do you have with carbs & ignition?
- What tools do you have available to evaluate and tune an engine?
Race Director
Joined: Nov 2006
Posts: 13,227
Likes: 7,823
From: Sunshine Coast, Queensland, Australia
2025 C3 of the Year Finalist - Modified
2024 C3 of the Year Finalist- Modified
2022 C3 of the Year Finalist - Modified
Cruise-In VIII Veteran
Not very clear on a lot of things. Rough idle, you say carb tuning. How is it you are certain of this?
what have you checked/tested to confirm this?
Have you pulled all 8 plugs? Tested all 8 wires? Ran a compression and leak down test?
Won't go over 60MPH. This is really, really bad.
We're still sure it's just a carb tune issue?
How do we know this?
EnquirIng minds want to know.
fuel delivery?
Have you checked/tested fuel delivery?
Have you checked, adjusted ign. timing to performance specifications? Have you tested the mechanical advance? Have you messured vacuum? Tested your vacuum advance?
Much more information needed.
Enquiring minds want to know.
what have you checked/tested to confirm this?
Have you pulled all 8 plugs? Tested all 8 wires? Ran a compression and leak down test?
Won't go over 60MPH. This is really, really bad.
We're still sure it's just a carb tune issue?
How do we know this?
EnquirIng minds want to know.
fuel delivery?
Have you checked/tested fuel delivery?
Have you checked, adjusted ign. timing to performance specifications? Have you tested the mechanical advance? Have you messured vacuum? Tested your vacuum advance?
Much more information needed.
Enquiring minds want to know.
Race Director
Joined: Mar 2017
Posts: 11,948
Likes: 4,506
From: Virginia
Pictures would help.
Videos uploaded to YouTube and linked in this thread would really help.
Start with timing. Do you have what you need to do timing correctly? If not, order an Innova dial-back timing light, or MSD timing tape.
Here's a helpful video to get you started.
Videos uploaded to YouTube and linked in this thread would really help.
Start with timing. Do you have what you need to do timing correctly? If not, order an Innova dial-back timing light, or MSD timing tape.
Here's a helpful video to get you started.
Melting Slicks
Joined: Dec 2009
Posts: 3,233
Likes: 657
From: Thunder Bay
All good advice here. Best to start with the basics. With that said, I would probably start by making sure there isn't a vacuum leak. These cars have miles of vacuum hoses and they deteriorate over time. Make sure the vacuum advance hoses are in good shape and disconnect and plug everything else and try it again.
