i have a 2004 sunfire with a broken timing chain 2.2 ecotech i put in a new timing chain it starts right up compression is 210 on all 4 cylinders dry-wet all 4 are 298 the engine is misfiring code po-0300 and po-141 when i let off the accelerator and back on it will backfire a little and it does smoke a little bit has any one ever had this problem before thanks for the info
That much compression jump at wet check would seem to me to indicate weak piston rings. Would also explain the smoking. I don't know how you avoided bending valves when the chain went south!