2007 cobalt

[coach74]

2007 chevy cobalt. engine light on, say engine power reduced and rpm needle jumps and car engine kind of shakes and jerks even when idling. i have a very basic obd meter that shows codes p0123 and po223. i have replaced the throttle body and the map sensor.

[carriedi]

did you clear the codes and the code came back or is the code just stored from your before readings?

since you have already replaced parts, you need to find a scanner that can graph the dtat stream and see what the computer is seeing. Sometimes the throttle body wire harness has problems. With a graphing scanner you can see if there is a break in the harness or a short. You would be able to see if you are getting all the information from the throttle body that you need to see. Or if the information is faulty. Also look at the fuel trims to see if you have a small vacuum leak. There is also a misfire counter that can see if certain cylinders are missing and what cylinder they are.