Air intake leak between the carb and the pistons action.
the closer the the carb, the more likely.
The engine itself creates Vacuum once it is running.
Sounds like a vacuum leak.
Auto Zone, Chilton shop maual.
http://www.customefis.com/emissions.html
what year is my 350 chevy engine K1201KRH
check for vacuum leaks
19 to 21 inches of vacuum at an idle, The higher the better. If the engine has a high performance cam then vacuum will be alot lower. When you rev the engine up vacuum should drop and then come right back up.
Chevy didn't make a 350 engine in 2001
Atk engines com or 350 Chevy engines com
Is the vacume for the distributor TIMED vaume or full vaume at idle???
6 to 8 degrees BTDC / Before top dead center. with vacuum advance pluged.
no