I have 1979 stock L48 engine. The problem is after the car sits for a week (weekend drives only) on start up the engine shakes rattles and rolls and smokes pretty good to until it warms up . After about 3 minutes of keeping your foot on the gas it finally runs and idles perfect. I have the stock Q-jet and the air intake air filter works the way it should (flaps and all). I am not sure if I should be adjusting the carb. or something else. I have replaced the plugs and wires last fall. Any help would be appreciated.

 

is the choke functional on the quadrajet? Hooked up? Just a thought

 

Yes the choke is hooked up and seems to be doing what it is supposed to do. The flaps are closed in the carb. and opens when it gets warm. I am a mechanical guy but when it comes to the carb. I know squat.

 

Mine does the same thing. When I took it to my mechanic, he said "The idle ports are clogged and its leaking gas into the bowl so it needs an overhaul". Haven't had it rebuilt yet. But I suspect choke problems as well. Try some carb cleaner and spray it in all the holes you can see.

If Lars or another carb expert is around, they should be able to give you more info and troubleshooting procedures.

 

not a carb expert....but try this next time try filling up the floats with
gas before you start it next time and see what that does to the routine?

 

Hi
Just a thought, except for the smoking, sounds like water in the fuel tank, especially since it driven occasionally.
Rog