You're forgetting about the most common problem if this is the little silver Nippendenso starter. Worn solenoid contacts. You'll get one rather loud clunk each time the ignition switch is turned to "crank", but it won't spin. The clue is it WILL crank eventually when you cycle the ignition switch enough times.
The starter will likely work off the engine because they draw so little current then that the worn contacts can handle that. Testing off the engine is never a reliable test.
There's four different contacts available for the solenoid. The "battery" contact is the same on all these starters on Chryslers and Toyotas. There's three versions of the "starter" contact and there's no way to know which one you have until you pop the cover off and look. I buy them from a local rebuilder for $3.00 each, and if the contact disc / plunger is needed, those are about 15 bucks. We have a local farm supply store that stocks the kits now with the plunger and all four contacts for 12 bucks. There's three different plungers too in those kits. Those you can determine from the parts books by the year of the vehicle but that's assuming you still have the original starter. If it was replaced it could be from a different model year. The Chrysler starters all interchange. There's two plungers that were used on Chrysler starters. One is about 1/4" longer than the other one. The Toyotas use a much longer plunger. Those have to be purchased from the Toyota dealer. So far I only HAD to replace the plunger once. On all the others it was just the contacts that were worn. If you're smart enough to remove a starter, you're smart enough to replace these contacts. Heck, even I can do it.
What you should do first though is to reinstall the starter, then use a test light to measure the voltage on the large battery cable right where it bolts to the starter. Keep watching the light while a helper turns the ignition switch to "crank". If the light goes out, there's a high resistance connection in that cable. With Fords it's commonly corroded strands of the copper wire hidden under the insulation right down there by the starter terminal. For other brands it usually bad connections at the battery. The clue there is the head lights and / or dome light will go out too when trying to crank the engine.
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Wednesday, October 31st, 2012 AT 9:55 AM