Hey everyone, new to the forums and looking for some guidance or help. My son purchased a 96 mustang GT automatic when he got it the security system was messed up. We sent the PCM off and had the security system bypassed. The car runs great now but when putting in gear it acts like its stuck in gear won't shift. We thought it may have been the solenoids, so we changed all of them and had the same result. Thinking it might be the transmission itself he bought a freshly rebuilt one and we installed it over the weekend. Went to test drive it and it is still doing the same thing. I am not sure what to try next, maybe the PCM isn't working correctly? Any advice you all have is greatly appreciated. Thanks in advance.