Tune up! A/C Compressor not working. Help!!!

I've installed a new optispark and a timing chain. The car runs great at idle and when it first take off, but when the engine gets warm, it start misfiring real bad and sputtering. When I put the engine back together I notice the A/C compressor wasn't coming on. I can jump it from the Fuse box and the compressor will come on. I put a new fuse in it and it still wont come on. Also, my engine light is on.

Also, my engine light is on.

Have the car scanned for codes, that's the first place to start. :2cents: