1994 S-10 pickup running rough

[northbendbob]

I have a recently purchased 94 S-10 4WD pickup - it is not running smooth on the freeway - it feels like it slightly hesitates or surges and when you give it say half throttle at 50 - 65 mph it really does nothing... you gotta mash it down and kick it down a gear or two to get it to go! I have owned it less than 2 months and have replace the transmission, fuel pump and filter. What should I do next?? thanks for reading and any replies, Bob

[V-8Fan]

Go with the obvious, basic stuff to start out with. A tune-up (plugs, spark leads, distribtor cap and rotor) may be all you need. But a compression check before you do any of this is likely a good first step before replacing anything (you're wasting time and money tuning up an engine that needs a rebuild), and you also might scan the codes from the computer also just to make sure everything's kosher in that department.

[northbendbob]

thanks!! willl scanning the codes tell me if an O2 sensor is bad? and also, do you advise genuine GM cap and rotor, or is major parts joint stuff ok? My local parts place ( Shucks) has a code reader, is it ok to let them plug it in to check it - or - should the dealer do it? thanks again, Bob

[V-8Fan]

Bob, you're welcome!

You can't always count on the codes leading you right to the problem, but I suppose it could work out that way. They at least give you a good place to start. I don't see any reason not to let the guys at Shuck's read the codes, and I think most parts chains do it for free. I don't know if a dealer will do it for free or charge you, to be honest, but I wouldn't want to have to leave my car at the dealer's all day long just to get the codes read. I think I would do the tune-up before reading the codes anyway.

As far as ignition parts go, you may be okay with a non-GM cap & rotor. Maybe the plugs too, but I have known of at least one individual who tried to tune up a late model Chevy pickup with a Vortec V-8 using the "correct" Bosch plugs, and it did not work. He went back to AC-Delco parts and the thing ran like new. Whether or not you will find the same to be true, I couldn't even guess. Your truck is a '94, and I am guessing you have the 4.3 Liter V-6...I don't recall whether the 4.3 Vortec was out already by '94 or not(wasn't in the V-8s until '96), but if it was one of the engines that they said you could go 100,000 miles before a tuneup, then I would spend the extra money on genuine GM parts. You can't go wrong that way.

Hopefully, the tune-up will cure the problem. Keep us updated!