1990 F150 5-speed standard 4WD

When I turn ignition switch to start truck, it keeps firing the starter, over & over again, turning the switch to off won't stop it, to the point that I have to stall the truck by putting it in gear to make it shut down. Thought it was the starter, replaced same, truck worked fine for a day and now same issue. Replaced the original key cylinder a year or so ago. Anybody have a direction to go in here? - ?starter again, ?ignition switch, key cylinder.

Thanks, aloha.

 

Sounds like your actuator in the steering column might be sticking in the start position. One way to find out is to pull the ign switch and use a screw driver to start the truck, then turn it off again, if it stays engaged, then use the screw driver to turn back further, if it disengages, then you know it's an adjustment on the actuator or the actuator is wore out....Someone else may have a simpler solution though.

 

Thanks, Mike; yes, sounds like I'm honing in on the ignition switch: INFO UPDATE - went out to try it again last night & battery was completely dead and HOT - both pos & neg wires hot, battery hot & when tested had only 5V! - ?sounds like a short in the ignition switch (and which could cause the actuator to stick on?). Thanks for your thoughts.

 

The actuator is mechanical until it gets to the module on the steering column. So either the ign switch itself isn't cycling back and forth all the way or the mechanic did not adjust the actuator rod/gears properly. The problem could be in the module but I'd look at the mechanical end first. Also just for kicks and giggles, did you try to put the old solenoid back on the truck? The new one may have just taken a dump. Maybe the old one wasn't bad, maybe you have a spare sitting on the shelf to try?

 

OK, finally got back to the truck (was away at work; returned home to find MANY bags of trash needing to go to the dump, so job one was getting the truck going.

Following Mike1's thoughts, plus some wonderful YouTube videos, plunged in: dropped the steering column, checked actuator rod (fine, even tho' lots of YouTube stuff tells you this rod breaking, esp in tilt wheel trucks, which I have, is a common item); replaced ignition switch (old one looked fine, but my electrical talents are replace-only and at 17 bucks can handle), reassembled the whole deal and...reconnected the battery and...immediately the starter started firing incessantly, until I disconnected battery again. First thought was that I'd screwed up reassembly of the actuator rod/ignition switch gear business and then, as I stared into the engine compartment, right below me was the ever-so-easy to replace starter relay...I wonder. Yep, that seems to have been it. Switched it out and immediately back to normal. Guess I could have whacked it with a hammer as, once removed, the old one has that internal rattle that I assume tells me the moving/disengaging part is not fused. Oh well.....all's well that ends well. Maybe this helps someone else with similar issue.

Thanks, Mike1, for your thoughts. Aloha.