Getting codes on my trans am after the heads cam install and tune po134,135 154,155 car runs great until the light comes on then the idle gets very rough...bad o2 sensors? have bad exhaust leak...can that be a possible problem?

 

Well those codes indicate NO activity from any of the O2 sensors. First check your wiring and all that stuff, although I doubt the wiring to all 4 sensors is bad. Where is the exhaust leak at? If it's close to the sensors then the leak could be affecting the voltage readings of the sensors themselves.

 

fix the leaks first dump the codes and see what comes back.
the o2s can't do there job with leaky headers

 

^^^^^this. Also Is the light flashing? When my o2 went out it would run like crap after it warmed up. And then would run better when the light came on because it was no longer looking at the o2 sensors.