HELP. Won't start

Drove home Wednesday after work just like every other day, no problems. Didn't try to start it again until Friday evening. Turn the key over and it sounded like the starter just jams into the flywheel and won't mesh with the teeth...tried again and the same result. Had the starter tested at two different auto stores and both times it checked out good. Re-installed starter and tried again, sounds worse this time. Battery has 12.5 volts, timing marks look good... I'm dumbfounded to say the least. Any ideas fellow Runners?? 2000 3.4 245k miles, 2wd auto

 

see attached image from '91 toyota fsm. i assume starters still work the same in later generations and the magnetic switch controls the position of the pinion. for some reason the pinion may be prevented from full extension. what does it sound like? slam, grind, spinning motor? did the shop test the starter with a load on it?or just install a different starter.

 

I would try swpping the battery out.

 

It sounded like the starter wasn't meshing with the flywheel. No, neither auto parts tested it under a load. I reinstalled it and it sounded worse. My next assumption was the engine wouldn't turn over. I pulled the timing cover and nothing out of the ordinary there either. Finally I used a 19mm socket to turn the engine over past the stroke it was on, about a quarter turn. Turned the key forward and it started just fine. No idea what happened or caused this but maybe I should carry that socket around from now on...It sucks not knowing if this vehicle will start every time I turn the key forward.

 

The battery showed 12.5 volts.

 

Yeah, i went down that road with my 02 and changed the battery out, then no more problem.

 

What was the initial problem? Similar to mine?

 

Yes sir.