2003 Chevy malibu engine jerking?

[Vincent C]

It feels like some of spark plugs are not firing but I am afraid it could be a mechanical engine problem. I am thing about taking it to the dealer for a diagnostic. Can you help?

 

[kelly_f_1999]

why take to dealer and be charged when autozone wil scan it and let you know what is bad for free and really any shop open in town would be cheaper than dealer most likely a bad tank of fuel id try a bottle of fuel treatment about 2 bucks and stay aways from dealer unless its covered and free since any shop can do work just as well and cheaper dealer last place to stop and you can replace a spark plug my wife does her own repairs like oil changes and tune up even brake jobs at home not hard once you know

 

[jetfan2]

I had this problem on my 2002 Impala. I scanned it and the scanner showed had a miss-fire on the number one cylinder. This was not the issue. The catalytic converter was bad, the front portion of it had broken internally and partially logged the exhaust port. Chevrolet has a service bulletin on this, if you car is included they will replace the converter free of charge. This could or could not be your problem, but it was what was wrong with my car. As usu-all GM will have a service bulletin on known issues rather than a recall, that was you may or may not bring them the vehicle, thus they may or may not have to fix it.