king80vette
Well-known member
My 1980 idles rough and has been this way for as long as I’ve had the car, 3 years now. It runs fine above about 12k RPM. Mechanics and other people have told me it could be a vacuum leak or the carburetor needs to be rebuilt.
It has the L48 engine, auto with 14k miles on it. The stock intake manifold was replaced with an aftermarket non EGR and the air pollution stuff was removed when I got it.
In an effort to fix the problem I have rebuilt the carburetor, replaced the intake manifold with the correct EGR GM one, installed the pollution stuff, replaced vacuum lines, gasket between the carburetor and intake, gas filter, cap, rotor, spark plugs and wires. I think that’s it.
When I was checking numbers I found that the distributor is a high altitude one. And I do not live in a high altitude area. Is there a way to confirm this, maybe on the build sheet? I have the history of the car and it was sold new in this state and has always been in this state. Could this be the wrong distributor for the car and could this cause the problem? The car also runs lean the ceramic on the plugs turn a reddish color. Do you think the carburetor should be re-jetted to give it more gas? If this truly is a high altitude car would the carburetor have been jetted differently then a non high altitude car?
Any help with this problem will be appreciated.
Thanks, Steve
It has the L48 engine, auto with 14k miles on it. The stock intake manifold was replaced with an aftermarket non EGR and the air pollution stuff was removed when I got it.
In an effort to fix the problem I have rebuilt the carburetor, replaced the intake manifold with the correct EGR GM one, installed the pollution stuff, replaced vacuum lines, gasket between the carburetor and intake, gas filter, cap, rotor, spark plugs and wires. I think that’s it.
When I was checking numbers I found that the distributor is a high altitude one. And I do not live in a high altitude area. Is there a way to confirm this, maybe on the build sheet? I have the history of the car and it was sold new in this state and has always been in this state. Could this be the wrong distributor for the car and could this cause the problem? The car also runs lean the ceramic on the plugs turn a reddish color. Do you think the carburetor should be re-jetted to give it more gas? If this truly is a high altitude car would the carburetor have been jetted differently then a non high altitude car?
Any help with this problem will be appreciated.
Thanks, Steve