I did not have the opportunity to adjust my transmission Vacuum Modulator today, however, I did take my abacus with me and got on the Interstate, and sure enough--my transmission is NOT shifting into fourth gear. I am now at a loss to explain this or to fix it.
I realized previously that I did not actually explain how to unplug the kick down solenoid. It is behind the pedal and just under the carpet. The switch for the kick down is the large black button. I had to lift the carpet up and reach behind it. It was a two prong plug with a catch on each side you had to squeeze to remove (I think, that was about a year ago).
You can also try unplugging the throttle position cable. I think it is located in a different place than mine, but it will also keep you transmission from shifting into high gear if it is stuck at "full throttle", except when you reach the red line for 3rd gear. For mine, this happens around 72-75 mph. Mine would not reach (and probably still won't) reach 4th if the kick down solenoid is plugged in.
I can't get the switch out. It does look like there is a release mechanism, but I cannot get it to work. I will give it another attempt in better light tomorrow, unless you have further suggestions on how to free it.
Just to be clear. The actual switch is still behind my pedal. I only unplugged the wire connecting it. I was at a gas station when mine broke, so I just reached back there are applied some force. Those connectors are pretty stubborn sometimes, so it may be corroded a little. As an alternative, there is a fuse for the kick down, and I think a separate one for the transmission. You could check those (or one) and see how they look. If the kick down is fused separately from the transmission, then you could unplug that one, although I don't know what other functions it will control. Good luck. and Merry Christmas.
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