Okay, I had this problem last winter in my '93 4Runner and solved it largely by just driving my '85 4Runner around. What happens is that as soon as it gets cold out, say in the low to mid 30's, the starter seems to first start spinning and then engage the solenoid. You can actually hear it spin and then hit the flywheel. This makes a heck of a racket I'm sure my neighbors love hearing around 5am every day. Generally, after the first grind it'll be fine and will engage like there was never an issue. Later in the day, if it is warmer it won't grind at all at start.
Around the end of last winter, I decided I needed to do something about it and stuck in a new battery. Oddly, that seemed to fix it. That is, until it got cold again.
Fast forward to this winter and the stinking thing started doing it again. I checked various contacts and wires and everything seemed to be working as it should. Getting frustrated I opted to just stick in a new starter. I picked a warmish day and stuck it in. Tada! No grinding at start-up....until the next morning after it had sat outside getting cold
Again with the checking wires and fiddling some with the ignition switch and I can't really visually see any issues and I seem to have good voltage from the battery to the starter. The new starter fits snuggly and acts up just like the old one.
I've thought it might have to do with the clutch cancel switch and tried starting it that way and that doesn't work. If it was grinding ALL the time it would make some kind of sense, but doing it only when it is cold outside is driving me crazy.
What makes it particularly annoying now is that I had decided to go with my old "repair" and I've been driving my old '85 4Runner. I've had this old dog just short of 19 years and it has something close to 250,000 miles on it. However, today I would guess I started losing a bearing in the transmission. A quarter million miles along with a 30lb flywheel may well have done it in.
Now, I'm stuck driving this cruddy old '93 until I figure something out and I need a real fix for it, but I'm stumped. I've gone through the FSM and surfed the net far and wide and I just don't seem to be able to come up with an answer.
Why would this stinking thing only do this when cold? Starter relay? Fubared ignition switch? Mysterious bad ground? Bueller? Bueller? Bueller?