Once in a while my GS will throw a CEL for cylinder misfire 1-3, only on cold start up. After it's warmed up, it drives and idles fine. I've changed all the plugs, changed the coils, only thing I haven't changed are the wires. I've also cleaned out my MAF sensor. Does anyone else have this issue?

 

Its has to be something that the 1&3 cylinder share. 300 or 400?

 

You may just need a simple valve tune up.

 

it's not all the time though... maybe 1 every 5 times of starting