Ok guys, need some help. My car started to sputter at around 1500-2000 rpms a couple of weeks ago. Did a search for "sputtering" and "misfire" and found that most were recommended at changing their O2 sensors. I just swapped mine out with some Walker O2 sensors and it still doesn't feel all there. Could this be a spark plug issue? Still the original plugs and my car just passed 10k miles. Recommendations? There has been no SES light since I swapped out the O2's. What plugs should I get. Just a few bolts ons so nothing fancy required I guess. HELP!!

 

Don't just throw parts at it, diagnose the problems. Misfires are usually due to plugs/wires. You can check to see if the wires are arching by getting to the darkest possible place at night and having someone rev the car up to where it sputters. Theres not much of a way to check the plugs without a GM scan tool...they can moniter each plug individually. If you want to just throw plugs at it use NGK TR55.

 

Just for the sake of it have someone check your fuel pressure. I had a similar yet more sever problem and it turned out to be the check valve in the sending unit of the fuel pump wasnt holding pressure and I had to replace the entire sending unit. Everyone told me to do the same, o2 sensors, plugs/wires, etc. Not telling you this is your problem but figured its a possibility. It is very easy to check the fuel pressure, you just need to get a gauge and connect it to the T that is attatched to the fuel rails under the hood. Only takes a max of 10 mins to hook it up.

Good Luck watever the problem may be

Vinny

 

Thanks for the replys. Unfortunately because I live here in the UK there are no Chevrolet dealers and the Vauxhall guys (owned by chevrolet) do not have the dianostic equipment for a Gen III motor. So I am at the moment stuck with throwing parts at it for the mean time. If the plugs don't fix it I will probably fork out the $$$ for a proper scan tool. Thanks for the help.

-Travis

 

mechanic here, and this is good advice. Could be clogged fuel filter or bad pump as well

 

I just pulled out the old O2 sensors I swapped to look at them again and the one of the right side (why i didn't look before I don't know) but it was covered with carbon. I mean this thing was BLACK compared the the one on the left. Could this mean anything?

 

???

 

bump

 

If the right side was really black, pull out your spark plugs on the same side and see how they look. There's a possibility that they could be FUBAR as well, which would DEFINITELY cause you're sputtering. Now, as far as what causes them to get black, I'm not 100% sure on, but I know it can have something to do with either running too rich or too much oil in the cylinder. Can someone else back me up on this?