engine trouble in the willys.... buick 4.1 liter

[Jeep Nasty]

My engine will start and idle fine other than it running very rich, lots of smoke when i step on the gas. When i try to start going over 40 MPH it starts sputtering and blowing lots of smoke and just doesnt want to run. ive also noticed that on hot days, that one the engine warms up for 15 minutes or so it will do this at even lower speed. so i really need some help form you guys over here that know these engines

the engine i have is a 1983 Buick 4.1L V-6, rebuilt about 40K ago, TRW alum. Pistons, .030 overbore, Cam Dynamics RV cam, sequential multi port fuel injection from Grand National Buick. The computer, e-prom, cal pack, mass air sensor are all new parts (2 year old).


I thought it may have just been a bad o2 sensor so i replaced that today but it didnt do anything. then with the engine running i disconnected the MAF sensor after reading a couple posts here and the engine sputtered real bad and eventually died, so i assume the MAF is OK....... so before i go replacing everything one at a time i was wondering if you might be able to guide me in the right direction so that i don't waste a lot of time and money. I do not have access to any type of scan tool and i have no way of doing the manual trouble code check since i do not have the buick instrument cluster of even a check engine light for that matter.

any help is greatly appriciated, or if you can point me in the rigght direction to get the help i need that would be great too.

thanks.

[Jeep Nasty]

ttt