[Oldsguy]

I agree with Jim, cable. You may be able to free it up if you can see and access where the cable passes through the firewall and be able to insert the nozzle of something like PB Blaster and "douche" the cable well with that, allowing the penetrant to fully saturate the cable. It should, over time penetrate enough to run all the way down, inside the housing of the cable and drip out where the housing terminates maybe under the floor pan someplace.