Hello, I couldn’t find anything on here with my specific problem (so if there is a thread please redirect me)

my automatic transmission has been acting up in my 95 SC400. Here is a list of things it is doing:

- jerky when shifting from 1st to second
- often will immediately shift to 3rd to low RPM, and I will need to press the pedal to to the floor to get it to shift back down and accelerate (and it’s jerky when doing that too)
- when I’m slowing down, from 3rd to 2nd gear there is a big vibration and jerk, and then another smaller vibration and jerk from 2nd to 1st as I come to a stop.

- generally, the vibration can be felt at low speed/RPM constantly as the car seems to always shift too quick/ be in too low of a gear for the speed.

my check engine lights are:

- sub-TPS (I can’t find anything on where that’s located, only the main one by the throttle)
- sub O2 sensors
- knock sensor
- EGR

Note: when I put it into ‘2’ mode, it shifts up and down both gears without any issue! This makes me think it’s a bad sensor somewhere

I just replaced the trans mount and it dampened the clunking but it’s still very present.

Please shout out any ideas if you have them. This is really getting on my nerves

 

Reads like a classic damaged ECU. When the capacitors leak onto the circuit board all kind of weird behavior ensues.

Best to start there. Rebuilt ECUs may be available. Best to take your original out and send it a reputable vendor like SIA or Tanin for repair. Expect a week to 10 day turnaround. Some of us (like me) have a working spare to deploy.

Once you have a working ECU start your troubleshooting from scratch.

 

thanks for the reply. I will look into it