I have a 1993 Maxima with 120k miles and is in good shape.

Well, my car sat for about 3 months and now that I have resumed driving it, my transmission shifts in all gears very late. Sometimes the problem clears up and it shifts normal, but then it goes back to shifting late again in a very unpredictable way. There is even a hesitation sometimes when it's trying to shift in the gear almost as if a wire is loose or something but I know that's not the case, it's just how it feels.

I took the car to 2 transmission shops and they told me they believe the problem is electrical. One told me to clean the mass airflow sensor, which I did, and although my car runs a little better, the transmission problem is still here.

So before I take the car back to the shop, what else should I do? What other transmission sensors should I check? Can I use the electronic control system in diagnostic mode to check for any faulty sensors?


One last thing, I changed the original electronic control system that came with my car. It's not parts matching, but I never had an issue up until now and I changed the box out about 2 years ago.

Did they scan trans for codes? If any codes are present then we can start there.

If it has set for a while it may have picked up stuff from bottom of pan. You could have a trans flush performed and see if it helps.

I fixed it... Unbelievable, it was really simple. I had tons on corrosion on my battery terminal and the negative cable was loose. So what happened was, when I drove the car, the computer would loose power and screw up the power control module.