My daughter's 2000 Cavalier 2.2 has very recently been running very rough in the morning, at idle and on acceleration. When the day heats up, all is ok. She had a P0300 code last week and a code P0304 yesterday. At first I thought bad gas, ran some water remover and gas tank/injector cleaner and filled up tank, thought this worked at first, but did not fix problem. My first guess is spark plugs and plug wires. The car has about 78,000 miles on it, bought it from the typical little old lady 3 years ago with about 30,000 miles on it and do not know if plugs, wires, etc. have ever been replaced. Also thinking that maybe I should replace the coil packs while I am at it.

Any thoughts on my situation and plan of attack?

Thanks...

 

plugs/wires good start. maybe clean egr and idle air control valve too. replace fuel and air filter as well.

 

Follow up, a bit late: new plugs and wires and cleaning one coil did the trick. Contact points on one coil were rusted for some reason...wire brushed it.

 

Yeah I was just going to say that sometimes there rusted and that causes problems with the starting and the way it runs. Usually them cavaliers work fairly well, but if it does brake[which tends to happen quite offten] there easy to fix and work on. Glad to hear you got it fixed, how is it working now?

 

Hope it works good for you now

 

Thanks, seems to be running fine.

 

thats good man.