87; 305 4bbl....guessing it may have somethinn 2 do with weather but..sometimes when i start my car it will just go to a real low idle and get slower then die...and the only way i can get it to start is by flooring the pedal..and it takes alot of cranking...i will usually pump the gas a few times before i crank it because it wont start without like 3 cranks if i dont pump the gas...and even when i get it to start its a real low idle and i have to floor the gas and the revs will slowly come up to speed

Choke plate work?

First, check all hoses and vacuum lines for split ends or have they dropped off their nipples? Replace any hose you suspect is not in good condition. Disconnect one end first, connect the other end last.

Cold start-up in the AM, remove air cleaner, and have assistant step on gas pedal one time. Look for two things to happen; 1) gas squirts out into the carb throat, 2) choke plate, the top plate, snaps shut.

No choke closing, unstick it, lube it. no fuel, replace the accell pump, (carb rebuild).

If the two events happen, maybe one more pump of pedal, car probably has a few miles on it, start engine. As soon as engine starts, its idle should be high, and choke plate should be pulled open alittle by the diaphram (choke unloader) on the passenger front corner of carb. Check to make sure hose is in good shape and has no leaks, replace if needed.

Andy,

You may also want to make sure the fast idle cam on the passenger side of the carb is raising up a bit as well. when i had a 86 z with the carbed 305 i had the opposite issue. it would start and stay high idle (1600 - 2000 rpm) and would not idle down at all. For a while i would have to pop the hood manually lower the fast idle cam and shut the hood. your issue may be the opposite, perhaps its stuck on the bottom end.