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I was getting a misfire code PO300 so, i changed plugs and wires thinking that mite be it and still have a misfire. Than I CHANGED THE COIL! Still have a misfire. SO NOW! I JUST CHANGED the cam sensor and still misfiring #2/#3 cyl. What can i do next? PLEASE PLEASE HELP! Kirk.
You appear to have eliminated all electrical (firing) issues. Check the harnesses to the injectors. If they are good, and you have no "U" codes present, it is time to do a compression test and a fuel pressure test.
Thanks T.R., We did that also it was good. But still no spark from #2 or #3 spark plug wire. im stumped:(
I had that issue on a boat. Check for a fuses leading to the coil. Each spark can be on it's own fuse.
Have you load tested the battery, checked fuses, and swapped relays?
Valve cover gasket? Any oil on the plugs when you changed them?
I have had this issue too. The gasket cover is easy to change.Quote:
Originally Posted by RicochetRandy
also checked for a vacuum leak or the pvc valve. sometimes those make it misfire as well.
Is there no spark or is it misfiring?
Pickles... there's no spark on 2 & 3...
Will check the fuses, relays and gasket cover after work today. Please keep all the suggestions coming!
Thanks
it may need a relearn if you have not gotten it to stop since you messed with the cam sensor.
So will it have to go to the shop for that?
yes more than likely it will. I will probably have the same thing on the car I am working on now. I have to replace the cam sensor and replace the head on it. So in a couple of weeks if you have not gotten an answer will let you know.
So how did this end up? Did you take it to the shop or did you find away to get it to work some other way?Quote:
Originally Posted by kirk
Our 2010 aveo has been dead in the driveway since 6am Christmas Eve 2013. Started running rough the summer of 2012, got error code P303. I changed the plugs and it seemed to go away. The very next summer, same thing, same error code. This time new plugs didn't fix it. Did some research and found a recall on the coil pack. Took it to the dealership and they switched it, and my new plugs out (threw them away with less than 20 miles on them), gave it back running just as bad as before. Long story short, it caused the fuel to run rich and carboned the innards all up and now it won't run at all. This is at 49000 miles, still under warranty, and they won't fix it. Needs new bank 2 O2 sensor and it's seized in. Can't get it out. AND the dealership didn't use anti-seize on the new plugs, cracked 2 on installation, and can't get them out either. Cat converter was completely plugged, cleaned it out like new and reinstalled, but I'm sure it's nasty from that point forward. Dealership and GM are of no help. Any suggestions?
Just want to clarify a few things - you have officially been denied warranty by the dealer and have called GM's Customer Relations and they too have denied warranty? This car has run rough for almost 2 years except for the past 5 months when it hasn't run at all? How did you arrive at the oxygen sensor diagnosis with a P0303 misfire code? The cat should have been warranty - how did they deny that claim? Please fill us all in.
I just replaced a cam sensor recently. I just reset my code and it worked no problem. I did not need a relearn.Quote:
Originally Posted by 05Aveo
Good deal. Glad to hear it was a easy fix and all. I got my head back about a week ago and havent had time to put it back on so this weekend if all goes well I will be working on it. Thanks for keeping us updated.Quote:
Originally Posted by xintersecty
I googled that code (P0303) and this is what was found. This site is for OBD-II codes and it is a #3 cylinder misfireQuote:
Originally Posted by Mechanicmom
If there are no symptoms, the simplest thing to do is to reset the code and see if it comes back.
If there are symptoms such as the engine is stumbling or hesitating, check all wiring and connectors that lead to the cylinders (i.e. spark plugs). Depending on how long the ignition components have been in the car, it may be a good idea to replace them as part of your regular maintenance schedule. I would suggest spark plugs, spark plug wires, distributor cap, and rotor (if applicable). Otherwise, check the coils (a.k.a. coil packs). In some cases, the catalytic converter has gone bad. If you smell rotten eggs in the exhaust, your cat converter needs to be replaced. I've also heard in other cases the problems were faulty fuel injectors.
So it is a systematic find. If you eliminated all the inexpensive faults, then choice your poison wisely. My mechanic that did my head said that some heads have seats that drop and this will cause the air to back feed through the breather and will cause the same problem. Not sure how they cleaned that catalytic converter but just cleaning the top will not cure anything and I would suggest that you take it to another dealer and let them do the warranty work but if you can't then I would certainly call GM and make a complaint and get them involved in the deal.
Wrong person. Kirk started the original thread. I just was offering my experience as in "what happen". It would be nice to know if he got his car fixed or not.Quote:
Originally Posted by 05Aveo
Sorry about that xintersecty.
Fixededed!!! Cpm was bad.