Another Truck Engine Question

[hobsiscool]

Ok, I have a new theory...bad spark plugs? truck runs, but tries to stall if i'm going up a hill...would this make it a little louder than normal? it runs kinda jerky i'd say when you try to accelerate...would this cause it to smoke while it's warming up...i'm just trying narrow things down..help! i know all I have to do is pull the plugs, but it's dark and cold outside and I won't get a chance to do it until this weekend so I was just wondering if this sounds feasible. Thanks!

[gchemist]

I had a similiar problem going up hills. Traced the problem to a bad fuel pump!!

[f.monroe]

My first thought was spark plug wires breaking down under a load . Second is a dirty fuel filter or some fuel delivery problem .
Frank

[piecesparts]

Maybe you should try a complete tune up and that way it gets all of the goodies changed out. A new set of plugs, plugwires and dizzy cap/rotor. Look at the fuel filter and see if the fuel pump is not failing you. Check the timing and make sure that you are NOT to retarded for the timing to work right. What color of smoke

[Cherub]

My money is on a fuel system problem.

[hobsiscool]

well i've posted several "what if's" already as to what may be wrong...A.) the fuel filter isn't in the stock location, it has been converted to an external filter, instead of the original location closer to the carb. B.) I really have no clue what kind of hell or highwater this truck has gone through before I got it, and no one really knows the answer. Where should I look first? Obviously the easiest is pull the plugs and inspect. My carb was just recently rebuilt which is when I started getting the problems. The smoke is a grayish color, and when it idles, it makes an abnormal noise, a clacking noise if you will. It starts, runs, and drives, but if you give it gas, it stumbles a bit, and tends to bog down a lot if you are on a hill. Is there a way to check for faulty dist. cap, wires, etc? Should I convert the fuel filter back to stock? Where exactly is the fuel pump located on this truck...81 GMC Step Side...4.1L I6...what should I look for...obviously i'm no certified mechanic, but I am intent on learning new things...if anyone has seen my previous posts, i'm used to working on my '05 Subaru Wrx Sti, so an 81 GMC Truck is a step out for me...but I love it...any more help is much needed, and much appreciated.

Thanks for all the replies thus far.