Heres my story:

I had a CEL and I checked everything out and I got codes for certain cylinder misfires, random cylinder misfires, an O2 sensor code and two codes for running too lean and running too rich. I went over my engine, replaced the spark plugs(which were shot), checked the coil packs which seemed to be fine and clean the MAF sensor. I also replaced the valve cover gasket which just cracked in my hands when I flexed it and I also replaced the O2 sensor. I had the CEL off for about 50 miles and now its back on! Reasons: Random Cylinder Misfire, System running too rich, and system running too lean. Im stumped now any help would make my day.

 

EGR system, very common the valve cloges up and dosnt work hence the fault code, allways tell the fault us code

 

Always tell the fault us code? haha that doesnt make sense. ha ok I know what that all means but how do I fix it?

 

??Anyone?

 

The performance of the car doesnt seem to be affected that much at all so im not sure what to do now!! Does anyone have any suggestions?

 

Check for vacuum leaks, which are boost leaks under boost.
Always give us the fault codes.