At cold engine(engine temperature not ambient) startups, the RPMs would not go up to 2000+ like it used to. Instead the RPMs go to about 1500-1800 RPMs, with the sound of some misfires. The CEL would flash about 5 times, then stay on. Once the engine is warmed up, there is no more sound of misfire and the car drives/idles great.

The CEL is a misfire on rotor #1(P0301). The spark plugs were changed 2k miles ago, ignition wires were changed right after the CEL started to appear, and the ignition coils were changed <10k miles ago by previous owner. If the engine was started when its still warm/hot, it starts and idles fine.

The car was recently in the body shop, where a new radiator was replaced and front body work was done. Any ideas on what I should check? What would cause the engine to not perform its standard "high rpm" idle on cold start up?

Thanks in Advance

 

Its warmer out, plugs beginning to foul because the engine runs too rich from factory.

Try cleaning the MAF.

Also, you need to redline it often to keep the plugs clean and engine carbon free.

 

Thanks, i cleaaned the maf about a month ago. I also redline at least once a day. This started happening about a week ago. Think i should reset the ecu and see if yhe cel comes back?