Just bought 1984 300sd with 245000 miles for $900...great car...tranny will only kickdown below 40mph and is not a function of microswitch under pedal...over 40 it will not kickdown at all.
Tried adjusting cable...was able to improve shiftpoints but still no kickdown. Is this solely the function of the solenoid or could I adjust the cable a bit tighter? I am afraid to overtighten.
How can I determine if the switch and/or solenoid are functioning?

Thanks in advance...