Ok, here are my two problems....Sometimes when I turn the car off, it wont shut off...it just keeps shaking like it wants to shut off but cant. Then sometimes its like my idle gets really low and I have to tighten that screw on my carb. Its like its vibrating loose or something. I have a 350 engine. My uncle keeps blaming bad gas. Any body got any ideas?

 

wild guess... maybe there is a vacuum leak that causes the car to shudder sometimes? Anyway looking for vacuum leaks doesn't cost anything and is a pretty good place to start.

by the way, what kind of carb do you have?

 

I have a edlebrock carb. I took it up to my uncles last night and he put some fuel cleaner in it. Now its idleing really high, has an aweful smell and backfires when i try to shut it off. I mean its loud!! it still studders when i try to turn it off.

 

If it's still trying to run when you turn the ignition off it's called dieseling...maybe check to see if your throttle is stuck open, timing is too advanced, or there could just be a lot of carbon build up in your engine. If all else fails switch to a higher octane fuel and it shouldn't happen.

 

ya thats what i did i no that it was the gas the idle screw was just coming
out because of the vibration on the car when it was shaking and
i went a did the higher octanen and no its running clean so idk what the problem was thnks so much for the advise is all of this seems people dont really no that much about older cars anymore its all 96 and up now a days

thnks so much =)

 

You've most likely got a vacuum leak and/or the carb is not tuned properly for the motor-throttle position is open too much at idle. Either condition allows too much air/fuel into the motor and promotes the dieseling. Higher octane fuel is more resistant to run-on and will mask the problem. Fix the problem and you should get better driveability, mileage and save money on less expensive gas.

I'd look for a vacuum leak first.