I have an 01 LS 75,000 miles. Just change spark plugs and wires. I got in my car today and there is this hesitation when I accelerate. I thinking it might me some bad gas but it drove fine for the first half of the tank. It feels almost like when you stall a stick. It seems to be doing it when I am going slower speeds. Any ideas?

 

Why did you change plugs? Was the problem there before you changed plugs, or did it appear after changing plugs? Do you have any codes or dash lights? What plugs did you use? What did you gap them to?

Answers will help narrow down...

But, something simple to check...make sure that all plug wires are seated properly. I know, it sounds dumb...but, it's gotten me before. Pull all the plug wires off of the plug and reseat them. The one behind the steering column is a pain.

Icarus

 

I changed the plugs because it was misfiring. I changed the plugs about two weeks ago. I took it to a shop to change because working on my car is a pain because you can't reach anything. I think I got some bad gas because I put some STP in it last night before I put in some gas and it is running better today. There is still a slight hesitation but nothing like it was last night.

 

Did you have a misfire code? Do you know which code it was? Was the cap and rotor changed with the plugs?

If it's good now, that's great. Let us know if it comes back.

Icarus

 

I had the po300 code the randon misfire. I didn't change the cap or the rotor that's next if it misfires again.

I will let you know if it comes back I'm driving from Pittsburgh to Ohio tonight so I hope that getting rid of that bad gas will take care of the problem.

 

Ashley, go ahead and change the distributor cap and rotor and be sure the wires are connected well to the cap. They can sometimes be cranky about going on solidly. If you were getting the P0300 code, I doubt that the gasoline is the main culprit. Also, if the fuel filter has not been changed, do so now. Let us know what happens.

 

No, no. I don't think the hesitation has anything to do with the p0300 code. That happened before I changed the plugs and then after. My car misfires in one spot in WV and that's it. The rest of the time it drives fine.

I noticed a hesitation yesterday and I think it was bad gas. I used one of those fuel injector cleaners and put new gas in it and is running better. The hesitation is rare. Last night every traffic light, there was a hesitation that was very defined. Today there is a slight hesitation, every so often. Last night I kept waiting for it to stall and today I didn't feel like it was going to stall. Does that make sense?

I changed the fuel fliter a couple of weeks ago when I changed the oil and filter.

 

Well we were all wrong. Last Wednesday it died on the side of the road. I had it towed to a shop and it all went down hill from there. They checked the plugs,wire, cap and rotor and they were all good. They ended up replacing the cam sensor, then they told me catalytic converter was plugged. I was about to have that replaced when they told me that I had a connecting rod knocking. I picked it up yesterday and it was running like crap. I guess I'm car shopping. I can't see putting the money in to fix it. I also found out that my 4 wheel drive went out sometime between last winter and now. I had it replaced back in 03.

 

REplace the cat and see if that dont fix your rod knock. The rod knock could be cuased by the backpressure the plugged cat is causing. Teh pistons are trying to push air out, however hte cat is stopping that from haopening, side effect is pistion knock from the air backing up into the engine.

Dont give up ont eh old girl yet.
4x4 fix could be real easy too. Could simple be a vacuum hose leak, $10 in new hose. Or it could be some other simple things.

 

I recently got a similar code, P0303 (Cylinder 3 misfire) right after I had some work done on my truck. The mechanic, not my regular one, said my flywheel needed replacing, which I didn't believe. At that time, I didn't know what code it was throwing, so I went to AutoZone to get it.

Once I knew it was cylinder 3, I checked the wire. Since the spark plugs were recently replaced, I doubted that was the problem. After I reseated the Cylinder 3 wire, the SES light went out. After a couple of days, it came back on. This told me the wire itself was probably bad, so yesterday I replaced all the wires, with AC Delcos. My Blazer is now flying again, and is running like new.

I guess the short version of the story is this: I still wouldn't buy what that mechanic said. He could have known all along that there was an issue with the wires, but told you something else to get you to spend more money. I would check all the wires again myself. Also, I won't settle for any less than the genuine GM parts for the ignition system. I might try the iridium plugs next time, but that's as far as I'd go.

Also, I browsed the Forum extensively before I did the job, to get pointers. I noticed a lot of people said the #3 is really hard to get to. I didn't have this problem, but it may be because of my tire size, because there was plenty of room between the wheel and the engine compartment. However, it should still be easy if you remove the front wheels. The key is to remove the air box first, then connect the wire first at the distributor cap and drop it down near the plug. Then reach through the wheel well to plug it in. And no, I didn't have to disconnect the steering column, either. But note that my truck is a '96. 98+ trucks may be different. I will check my wife's Jimmy to see if there are any differences, but I doubt it.

I actually had more trouble on the passenger side (#2, 4, 6), because of all the hoses. Even so, I was still able to replace the wires without removing any hoses. Just disconnect the wires at the top first, then gently pull them out through the bottom. As long as you just do ONE AT A TIME and be patient, you will be fine. I got it right the first time without any problems. Good luck!

Raphael