So I recently changed my spark plug wires on my 1993 FZJ as well as doing the dreaded PHH replacement yesterday. When I was done replacing the PHH I went on a test drive to make sure I had no leaks and it was good. However I noticed that when I got on the gas the engine would rev up slowly and it felt like it had no power. The check engine light also came on. I later discovered that if I shifted into Low it would stay in low until I manually shifted into 2nd. If I tried to shift it from 2nd into drive to get into 3rd/overdrive nothing would happen and it would stay in 2nd. If I were to stop and start out in Drive it would stay in 3rd and not downshift to get on the move faster. That same day I took it to the dealer to see if they could diagnose a problem and they said that it could be a bad knock sensor (this was the only code they got from the check engine) but I believe this may be irreverent to my problem.