The passenger side butterfly on the air cleaner snorkel may be sticking closed.
This after engine is up to operating temperature. I took the duct off while engine was at idle.
Does it open under acceleration with vacuum ? 1979 -L-82.

On my '81 when I had the stock engine and air cleaner, I remember that my passenger side only opened under full throttle conditions (no vacuum). Maybe '79's where the same. I put a "TEE" inline with the vacuum line that controlled the drivers side butterfly. So then both opened as the engine warmed up.
Sarge

Sarge - Thanks !

Sarge's tip will open both flaps quicker and may help warm accelleration. But it may cause some cold driveability problems. Look under the flaps, one will have a tube to the exhaust manifold stove (metal around the manifold) This is to pick up hot air when the engine is cold, and make fuel atomize better. It helps cold throttle response. Without it, or by opening both flaps, you may get a cold hesitation. The good news is you can adjust the choke and compensate, and eliminate the hesitation and still have the full operation. Just backoff the choke pulloff a small amount, and maybe tighten up the choke coil a touch. Why didn't Chevy do this? Emission regulations. By the choke opening less and slower, it pollutes more on warmup. I'm good with that. If you car is over 25 years old no one but California cares about this. Less then 25 years and the Federal EPA cares. If they don't inspect for this in your area, good. If they do, they are not likely to catch it anywhere but California. Just some background. I'd say go ahead and do it, then adjust the choke if needed. It may be fine without the adjustment.

Ken Styer

|UPDATED|1/24/2004 3:43:11 PM (AZT)|/UPDATED|

Thanks Ken, appreciate it. Here in FL, emissions not much of a problem. You should see some of the oil burners on the road down here.