1991 Automatic Transmission Issues.
 

Hello!

I'm having huge issues with my auto transmission on my 300zx. A little while ago I had an issue where the transmission stopped shifting from first to second and finally I wasn't able to shift it out of neutral. I brought it to a transmission shop where they said a swap would be required, so I bought a new (used) transmission and had the swap done. Only a few days after the swap the transmission again will not shift out of neutral (it will shift into first if I turn it off and on again a few times, but it wont shift into second). It would appear that after the swap, it made no difference in the transmissions performance. What could possibly be my problem? Thanks in advance.

If you have access to a known good ECU, try giving that a swap. Don't go out and buy one before trying though, pretty expensive and it's a big IF.