Help me diagnose - bad starter motor?

So I tried to drive away the 'rolla from work at lunch, it gives three half-assed cranks and then nothing. I give it another turn, one little crank and then nothing. Another and the tach just twitches a little, and that's all it did from then on. I have a little battery condition meter plugged into the cig lighter that says "good" so I took the most hammer-like tool I had and gave the starter motor a few whacks, no difference. I got the office security guard and some construction workers on the lot to give me a push-start, fired right up and ran fine.

I parked it on a hill when I went to get lunch but I tried cranking again to see if there was any difference. Same thing, tach just twitches a little, no audible cranking. So I gravity-start and drive back with no problems.

I checked the battery voltage with a voltmeter, it shows 12.9 volts between the two terminal clamps.

The fact that the starter motor's at least moving enough to cause the tach to twitch suggests the electrical system leading up to it is good. It's a dead starter motor right?

Check it's ground and the ground to the block. (although it sounds like possibly a bad starter.)

98% of my toyota starter failures (like you describe) Have been the contacts in the starter, remover the starter, pull the little plate, and take a look. They were available from toyota, for little $. HTH

Check the voltage at the battery while trying to crank. It wouldn't be the first battery I have seen that "looks" OK when you check the idle voltage and looks pretty dead when you measure the cranking voltage.

I checked the voltage with the car off, not idle.

I'll have to check the rest when I get home, man is this a bad time for this to happen...

warpedredneck wrote: 98% of my toyota starter failures (like you describe) Have been the contacts in the starter, remover the starter, pull the little plate, and take a look. They were available from toyota, for little $. HTH

this is worth a look... And not just on toyos... clean the burn marks of the contacts and go for it...

Yeah, checking voltage without load is pretty much useless.

GameboyRMH wrote: I checked the voltage with the car off, not idle.

Sorry, I think I wasn't too clear in what I meant - I was referring to you checking the battery voltage with no load on the battery so it was sitting "idle".

I've seen batteries showing that sort of voltage with no load and then drop the voltage to 8V when trying to crank the engine. That didn't exactly help with starting the car.

Condition of the battery terminal connections is the main source of cranking problems. the battery voltage should not drop below 10 V. while cranking.

Voltage at the battery while trying to crank is the same. The voltmeter I have at home doesn't do fractions but it's still 12v. I guess that means there's a wiring problem to the starter?

Starter relay?

Update: Starter motor and solenoid were both bad. Cranks way faster now.