After cycling the key to check codes no longer shows code for misfire. Now shows codes 172 (fuel control sytem too rich), 135 (upstream o2 sensor bank #1 heater failure), and 32 (upstream o2 sensor bank #1 heater voltage too high).
Thanks for help so far.

 

Hi , I'm An old retired tech ! I was thinking after all the post . It might be a mechanical problem ? Let your engine cool all nite . Then remove # 3 spark plug . Cover the plug hole in the head tightly with your finger an have your wife spin the engine over ! If you get a compression loud pop from the hole your valves are sealing an should start. If not pull the valve cover an look at your push rods & rocker arms for damage . If you don't see any damage start the engine an look & listen for noise or damage or see if the valves are moving up & down as your cam may be broken or just worn out . My thoughts Bud

 

Checked compresion with gage on all cylinders 190 on all but cylinder 3 it only had 30. I'am going to pull vave cover and check push rods & rocker arms. I will let everone know what I find. Just in case its the rings which do you suggest new piston and rings or new engine. Where would be a good place to get an engine.
THANKS

 

If the problem is the piston, you would need to remove it to inspect the cylinder bore. You could also have a burnt valve too.

 

Checked vavles and they are in good shape done fluid test on #3 cylinder and compresion went up. So from what I have read and heard that means bad rings.
Where would be the best place to order a motor from. Thanks for everone's suggestions.

 

Yes, rings but also could have cylinder damage on the thrust sides.