Ford Taurus Repair Question
Some components work only when car is in "park" or
Answer
you will definitely need wiring diagram and a DMM to go hunting for the short in the electrical system within the components that are acting weird
Sounds like the mlps sensor, otherwise known as the neutral safety switch, could possibly be raising havoc... it's on top of the trans, under the airbox hose, bunch of wires running thru it,, along with the shift linkage relatively easy to replace, there is some sort of alignment tool your're supposed to use to set it up correctly,, this sensor has been known to create really weird goings-on when it fails..
The neutral safty switch allows curent to pass from the starter switch to the starter when only the lever is placed in P or N.
Some neutral safty switches are nonadjustable.If theses prevent starting in P or N and the gear selector linkage is correctly adjusted, They should be replaced.