Not the kickdown switch
 

I have searched this site and have not been able to find exactly the issue I am experiencing.

I have a 1991 420 SEL with a 1988 560 SEL motor. I just adjusted the Bowden cable and the car shifts perfectly and part throttle down shifts are working great also. Full throttle down shifts are not functioning correctly. I replaced the kickdown switch under the accelerator pedal. As a test I engaged the AC compressor and depressed the switch by hand and the compressor continues to run. Also under full throttle acceleration the car shifts from 1st to 2nd at 4500 rpm and from 2nd to 3rd at around 5000 rpm. Any ideas what could be causing this. are they related?


Thanks

Also, the first gear start switch on the shifter does not work though the car will kickdown to first from a stop under hard acceleration.

With the engine running, either depress the kickdown switch OR lock the parking brake & shift the trans into the "B" lock position & check the kick-down solenoid for POWER with a volt meter.