ok im new here and im not quite sure where to post this so a moderator can move it if you like. so im purchasing a 89 supra privately and ive got a question about the transmission on it. i went and had a look at the car and had a test drive it seemed to shift with no flaws, i must have drove it for about 15 min, so i told the guy that i would buy it under the condition that he would send me a copy of his safty certificate because he forgot to bring it with him. So as he was driving home today he noticed the transmission acting up he said that he would stop from rest and accelerate and it wouldnt shift when its saposed to, it would rev aroound 5000rpm and he would let off the gas, then push the gas, then let off, then push, then let off and he would do this about 8 to 12 times. He says that it shifts into all the gears with no shift shock. i personally think its a sensor of some kind, he describing classic symptoms. Let me know what you guys think, i need all the help i can get. Thanks.
89 supra Transmission problem
- Thread starter danthomas11
- Start date
If he had a TV cable, I would tell him to adjust it. But we don't so pull codes and look for the speed sensor.
Last edited:
Nick M said:
TV cable?
Ya its a non-turbo and i taught him how to do the codes from the site and he will be doing it tonight with a friend that rebuilt his transmission, when he finds out he'll be bringing it to mr.transmission tommorow after his work.
Throttle Valve, Our line on the throttle is only used to raise main line pressure.
I will back up a bit. When you accelerate, the cable pulls on throttle valve. As the speed increases, the governor valve creates more pressure than the throttle, forcing an upshift. When you put the pedal to the floor, the throttle pressure shoots up over governor pressure forcing a downshift. It has been a while, but I think that is how it works. On ours, we have a speed sensor and input from the TCCS engine computer, such as throttle position sensor to control shifting.
I will back up a bit. When you accelerate, the cable pulls on throttle valve. As the speed increases, the governor valve creates more pressure than the throttle, forcing an upshift. When you put the pedal to the floor, the throttle pressure shoots up over governor pressure forcing a downshift. It has been a while, but I think that is how it works. On ours, we have a speed sensor and input from the TCCS engine computer, such as throttle position sensor to control shifting.
im buying the car to start learning, im only 17 and i can rebuild a motocross bike with my eyes closed. I havnt even really WORKED on a car before, other than my auto class but that was all about changing tires and making sure the air pressure was right, baby stuff.