Rough idle after choke opens

[dblhh]

My 1977 TA has a Pontiac 400 with the Quadrajet carburetor. After it has been parked for awhile, you can start it up and it runs just fine with a smooth idle. After about a minute -- it seems about the time the choke opens up -- it begins idling really rough and will barely keep running. While the engine is warm, it continues to have a rough idle everytime it is started. Is this likely a problem with the carburetor or something else?

[Cliff Ruggles]

Have you tried adjusting the idle mixture screws after the engine is fully warmed up?  The symptoms indicate a lean condition at idle......Cliff

[dblhh]

Have you tried adjusting the idle mixture screws after the engine is fully warmed up?  The symptoms indicate a lean condition at idle......Cliff

Cliff,
Thanks for the reply.
No, I haven't tried adjusting anything on the carburetor yet until I had an idea I was looking in the right area for the problem. I'll give it a try.
Thanks again,
Herrel

[Cliff Ruggles]

"but when kicked down off of high idle. the engine wants to slowly die."

This often indicates the timing is falling off and may be combined with a lean carburetor condition, choke pull-off opening the flap a bit too far, etc......Cliff