I have an '83 350 with HEI distributor Carb'd. Mallory distributor, MSD wires, Accel header plugs & Holley 670 Truck avenger carb are all new. I've noticed when it's cold (below 35*) & rainy the engine will not stay at fast idle for long. It gradually declines & theres a noticeable smell of gas from the exhaust. I have to give it gas to get it warm, then it still wants to stall when I stop at lights until it's been running for awhile. If the weather is warmer & still rainy it idles ok doesn't give me as much trouble. When it's warm & dry I have no problems, idles up & stays there until I tap the gas. All of this happens without me touching any thing on the vehicle, just mother nature's influence. What's the deal? Any help would be great. Thanks.

auto choke ? sounds like a choke spring to me. unless your gettin' moisture in your dist cap, its got to be carb related .my 2¢

Adjust your choke for cold weather, basically, loosening 3 screws, and turning the choke spring cover CCW (towards the rear of the vehicle IIRC) and that should fix your problem.

I'd turned the cover some, I'll turn it some more. Oh yeah the carb is a 670 truck avenger the good one not first the gen.

lol...I had the old TA it was dumb, a veritable POS.