Udderly Annoyed

[jrock82]

Ok so I have a 94 blazer with a vortec motor and Im not quite sure what the issue is. I can be driving down the road and my truck will begin to sputter(and significantly decelerate) if I get heavy into the gas. Sometimes it will cause it to backfire. I replaced plugs, wires, distributor cap, rotor button and ignition coil and it was running great about a year ago. When this particular problem first started, ignition was the first thing that I checked but everything still appears to be in proper working order. I also recently replaced my fuel filter since it didnt look like it had ever been changed. The troubling thing about the way my truck is running is that there is no rough idle whatsoever and sometimes it will run with no trouble. In fact it still runs like a scalded dog when it doesnt sputter. It seems like if I sit in traffic and let it idle long enough, it will start to do it. I didn't really pay the sputtering much attention at first. In fact I just dismissed it as being due to bad gas. I have changed brands of gas three times so, Im pretty sure bad gas can be ruled out. Before today, this was just an intermittent problem but now it seems like something serious is wrong. I havent been able to get it above 50 anywhere I have went today and it has just cut off on its own twice. Im just not real sure what else it could be. Im hoping that someone can give me some insight on how to resolve this problem.

[Carder09]

You drop the gas tank and look inside for crud? Though you may have changed all those parts, still crud can be movin through the fuel system cloggin up the line.

[ntg]

You said "vortec" in it...so did you have a new motor put in it? Just want to make sure because they didn't put the vortec in the '94s...they we're all TBIs....wait now I see you've got a s-10 blazer. Still which engine do you have in it exactly? I'm guessing the 4300 vortec L35?

[rodram]

other things to check:

- is your catalytic convertor plugged?

- maybe fuel pressure is low... but you would usually have trouble starting the engine before having the poor performance you describe.

[92rado]

Kinda sounds like the coolant temp sensor. I had a 4.3 that did something similar.