so we change the motor in a 2007 cobalt with one from a 2008. when we tried to start it it wouldnt do anything. so we took the wiring harness from the 2007 motor and out it on the 2008.. starts and runs great now. problem engine light came on when we tried to read the code the scanner said no communication. i read that the emc and lighters are on the same fuse but there is power to the cig lighter. so figure the fuse is good. we played with all the plugs and grounds ( fo?und one loose) but didnt seem to make a differance. any ideas?