1995 gmc sierra, 1/2 ton, 2wd, 4.3, 5sp

About 2 years ago it started running rough, not to bad but it wouldnt idle very well. it has been driven infrequently since then, maybe once a month. Today i tried to get it going, but it wouldnt idle, and when accelerating it jerks, and has a noticeable loss of power. it has new cap, rotor, plugs, wires, and fuel filter. im at a loss.. could the timing be off, or maybe a bad sensor somewhere? I was told to try draining the tank, because i live in phoenix, and the winter day / night temp difference can cause alot of condensation to build in the tank. (i know that happens in airplanes).

any thoughts.. suggestions.. this truck is my baby, ive had it for 9 years.. though ive neglected it the past 2 years.

thanks in advance

1995 gmc sierra, 1/2 ton, 2wd, 4.3, 5sp

About 2 years ago it started running rough, not to bad but it wouldnt idle very well. it has been driven infrequently since then, maybe once a month. Today i tried to get it going, but it wouldnt idle, and when accelerating it jerks, and has a noticeable loss of power. it has new cap, rotor, plugs, wires, and fuel filter. im at a loss.. could the timing be off, or maybe a bad sensor somewhere? I was told to try draining the tank, because i live in phoenix, and the winter day / night temp difference can cause alot of condensation to build in the tank. (i know that happens in airplanes).

any thoughts.. suggestions.. this truck is my baby, ive had it for 9 years.. though ive neglected it the past 2 years.

thanks in advanceYou can buy gas dryer at auto parts store. It will remove condensation from you gas tank. If they don't have any, look at the fuel injection cleaners, a lot of them will do the job.

i put in 2 8oz bottles of stp injector cleaner... the check engine light came on, and flashed two codes 35 and 44

35 idle air control
44 lean exhaust

is there a way to clean the idle air cotrol valve.. or must it be replaced?

i changed the egr valve and selenoid, and the coil today but to no avail.. ill try the iac tomorrow.

How long since it has had a throttle body rebuild/clean? Could be some carbon got into that IAC...

For some reason it thinks it is running to rich and is leaning out your exhaust and cutting down your power... How bout your Oxygen sensor? Ever change it?