2002 Chevrolet Silverado w/104K, 2WD, still running rough

Rough is an overstatement. When idling you can feel and hear the engine isn’t quite running as smoothe as it should. Wife even notices it so I know it’s not my imagination. Replaced plugs with OEM and it’s still there. Could it be a wire and how do I check? Or do I replace all wires?..On another subjuct, Got 2 new tires and the shop told me I needed new shocks. For real or a scam?? How do I test. Truck ride is smoothe I thought.

As for the rough running, do you have a driveability problem with the idle problem? Any check engine light? Codes? The wires should be replaced with the plugs, and I believe are only sold in a set of eight, so you might as well replace them. Cleaning the intake/throttle body/IAC would be a good thing to try. Another silly question: did you gap the plugs or just put them in there? Many people assume the gap is set, but it’s not, with the exception of those goofy multi-prong Bosch plugs the parts vendors are always trying to shove off on people.

As far as shocks go, at 104k miles, you are certainly due. Tread wear patterns will tell you a lot about the condition of the shocks. If the old tires are cupped or scalloped, the shocks are shot. You could also jounce each corner of the truck and watch the rebound. If you get it jouncing with all your weight and step back and watch it, each corner should rebound no more than twice, ideally once. If it bounces three or more times, they are shot. Periodic replacement of the shocks is not a scam. You will probably notice an improvement in the cornering and braking ability of the truck if you get them replaced.

I had the same problem-99 silverado 2wd. Changed plugs and wires - no change. Had injectors cleaned - runs great. I have 175000 miles, same struts.