On this 2000 Pontiac Grand Am,Se.it has a 3.4liter engine. I took the head off an replace the head gaskets.I sent the heads off to be check both heads needed work on.after putting them back an torque spec at 44,and than another 95degree trun.this engine had ran hot, an one of the head had a dime size peice broken in it .the car will crank but it backfireing real bad,so can you help resolve this problem.
Gordon jones....