I have a 2001 4X4 150 that is killing me. I have changed the battery, solenoid, ignition switch and starter all twice and checked the wires for continuity. My starter won't disengage. Any ideas?

 

Welcome to the forum!

I'm thinking it's in the ignition switch even though you have replaced it. Once you turn the key it sticks?

 

The starter not disengaging could be one of a few problems. Either electrical or mechanical. Either it is getting power when it should not, or the issue is mechanical. I have had it in the past(but not on a ford) where the drive teeth were too tight on the flywheel teeth making it not disengage, and I also had it where on a customers vehicle, I had 4 defective starters in a row, before I switched suppliers to get a good one. You need to do a better diagnosis.