I see you are going through alot of work trying to find the problem.....and at first, one would think that maybe the mouse varmits had knawed some of the wiring.....that would royally suck.

However, you say that the starter does not want to disengage......that is a big red flag. You are saying that at times it cranks, and starts, but the starter does not disengage from the flywheel as the engine is running? If so, maybe you just got a bad starter/solenoid going on?
Are you sure the new starter that you put on was the exact part for this Montero? Not a different depth on the starter nose gear or something different going on?

Bizarre stuff happening......I would like to hear input from others on this.

You are right.....the ECU should be right behind that kick panel, same as on my 94 Montero.

 

Update. I have cleaned and made sure all connections are good and it starts right up now. However, the starter is still making noise while the engine is running. (Attached google drive video below.)
from what I was able to dig up, it seems that the starter isn’t a matching part.

factory #: M379687D
replacement #: 17131N

I guess this is a somewhat known issue that parts stores don’t verify the numbers and sell the 1st one that pops up. I will be trying to find the correct part this weekend and see if that will fix it 🤞🏼

https://drive.google.com/file/d/1gND...w?usp=drivesdk

 

Good video you made. I am guessing that the plunger gear that turns the flywheel is not retracting all the way, and keeps spinning along with the flywheel. Very well could be the wrong part which does not quite meet the specs of the factory starter. I hope the new one solves that problem.

Great to hear that cleaning all the cables worked.
Good luck with it.

 

Just curious - when you replaced the starter, did the teeth on the flywheel look good, or were they mangled up somehow? Having damaged teeth may prevent starter disengaging properly. Wrong starter will definitely contribute to it.

 

Still having issues. I did get a new starter that my parts guys swear up and down it’s the right one. I plugged it in and it still made that terrible noise so I tried seeing if an alignment shim would work if it wasn’t retracting enough and no dice. I pulled the whole front end of the engine bay out so that I could get to the crank pulley so that I could rotate and check the flywheel. No damage as far as I could tell. And I ruled out electrical issues because even after pulling the contract wires after starting it still made the “grinding” sound and wasn’t disengaging.
it’s got to be a problem with the starter itself right?
the starter diagrams I’ve seen show a different bolt pattern on the starter than the one I have but shows that it’s discontinued. I’m half tempted to steal the starter off my neighbor’s montero just to check lol

 

I just watched your video again......and now Im thinking that you might have a nut or bolt rattling around beside the flywheel.....or maybe a piece of gravel? Im not sure how many bolts and what size hold the flywheel on, but maybe one of those has backed out and is clanking around as it taps against the flywheel. Is there anyway to access the lower area of the flywheel and stick a magnetic pick-up tool in there and see if you can retract the offender?

 

Hunter.....take another listen to his excellent video above.......do you agree with my last comment above?

 

I am puzzled with that sound, I find it hard to believe that a flywheel bolt would be able to come loose in there. On these vehicles the spave is super tight. The steel bolt would smash the aluminum casing if it came out even part way. I suppise one should open the access cover, rotate the engine and check every bolt just in case. Perhaps a piece of old starter gear tooth making that rattle?

 

Yep.....my ear tells me that its not a problem with the starter, but something rattling around beside the flywheel.......my ear is thinking about a 14mm bolt with decent wear/tear on the edges.......or could it be a stubborn piece of gravel?

 

BKCaspy95.......So, please tell us what you found. Loose bolt?