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TH400 has electric kickdown- the switch is mounted inside the car on the bracket for the go pedal. In a quiet spot, with the key on, you can manually operate the switch and "sometimes" hear the solenoid in the trans click. Key word is "sometimes".
Other than that, key on, check for 12v at one side of the switch. Good power there, then pull the connector off of the left front of the trans and check with a 12v testlight while someone pushed the pedal to the floor.
I got a 66 Catalina vert for free a million years ago cuz it needed a trans. The kickdown valve got off center and stayed in downshift mode. Cleaned it up and sold the car for 300 bucks! Something to watch for if a turbo 400 won't upshift.
How often is the switch itself at fault?
Or could it also be that is does not move all the way needed to get activated? (it needs some WD40?)
Sometimes the carpet / underlay / mat gets bunched up a little under the gas pedal and may prevent it from going fully "floored" so there is a possibility the switch isn't getting hit. As mentioned above, try testing it by hand and see if you can hear the solenoid (not totally sure you can do this without being under the car...)
Pull the lever on the switch forward and it will reset when you press the pedal to the floor next time. Not really adjustable other than that
M
Sometimes the carpet / underlay / mat gets bunched up a little under the gas pedal and may prevent it from going fully "floored" so there is a possibility the switch isn't getting hit. As mentioned above, try testing it by hand and see if you can hear the solenoid (not totally sure you can do this without being under the car...)
Pull the lever on the switch forward and it will reset when you press the pedal to the floor next time. Not really adjustable other than that
M
I can try to reset the the switch... So, I just pull the lever forward...should it after that like snap backwards right away or something?
Last edited by cromwell74; 06-12-2018 at 12:14 PM.
more or less
Pull it forward (towards the seats) and them press the gas pedal all the way down, that will set it to the position it needs to be for it to activate.
Some people have also added a piece of rubber tubing over the pin on the switch to have it activate slightly earlier as it effectively makes the pin larger so it gets hit by the pedal sooner.
Once all of the items above are checked and working properly the kickdown solenoid (valve) inside the transmission can be defective/worn out. It is not hard to change if necessary.....it may be time to change the fluid and filter also...….
Be sure to test the new solenoid while the pan is off the transmission. to make sure it is working properly by pressing on the accelerator pedal (with Key ON/the engine OFF)…….
Last edited by doorgunner; 06-13-2018 at 10:33 AM.
more or less
Pull it forward (towards the seats) and them press the gas pedal all the way down, that will set it to the position it needs to be for it to activate.
Some people have also added a piece of rubber tubing over the pin on the switch to have it activate slightly earlier as it effectively makes the pin larger so it gets hit by the pedal sooner.
M
Yes, I got this solved (I think...I have not driven the car yet)...the switch was not moving all the way to activate so I put a rubber tube over the pin on the switch and now I can hear this click from the solenoid when I press the pedal to the floor.
Yes, I got this solved (I think...I have not driven the car yet)...the switch was not moving all the way to activate so I put a rubber tube over the pin on the switch and now I can hear this click from the solenoid when I press the pedal to the floor.
06-11-2018, 01:33 PM
No kickdown today on my C3 -74
