I've recently purchased a well-used E150 Econoline Van with about 130K miles on it. Straight-6 carbureted.

After I bought the van, I noticed that the air filter housing was slightly detached from the top of the carb (allowing LOTS of unfiltered air into the carb) and that the air filter itself was very dirty. I replaced the air filter with a new one and re-attached the air filter housing and now it runs very poorly at low revs.

Its been mostly ok, but just yesterday it stalled and wouldn't restart on a slight upgrade. After several start attempts (and lots of gas-smelling smoke), I DETACHED the airfilter housing and the thing just started up and ran like a champ. It seems as if the thing needs a lot more air to run properly. I'd rather run with an airfilter than without, so leaving the airfilter housing detached is not tolerable.

Does anyone know what's going on here? The TAC seems to be working ok -- the over-rich, poor running condition exists even when the TAC trap door is in the full-open position.

Thanks for the help. I'm a newbie car mechanic, but have been working on motorcycles for years. I hope someone can point me in the right direction.

Thanks, Matt

 

I would see if the aircleaner is interfering with the choke. Maybe it's not the correct air cleaner?