My 1991 780 Bertone Coupe has not been starting when left on the parking lot in the sun. I've replaced 2 starters this summer but it still keeps happening. My mechanic is stumped. The only comm

Sounds like a corroded connection somewhere, start with the easy ones, battery, cables, coil and starter connections at the starter. also check the distributer cap and rotor if the engine cranks but wont start. good luck with that, glad 2 c someone keeping the old toyotas running, u should be able to get close to 275k mi. out of it

CHECK BATTERY CONNECTIONS, STARTER CONNECTIONS, WHAT DO YOU DO WHEN IT DOESN'T START, TO GET IT GOING AGAIN, DO YOU GET A JUMP START IF SO CHECK CONNECTIONS.

Try to check your fuel pump pressure, or replace the fuel pump

Check the distributor

how long did the starter last for that you bought ??? if its still under warantee then get it replaced as thats where your problem is at

First things first, if you can not turn the key lock past ACC you are not doing anything with the starter. The problem with the lock must be in the lock or the linkage connected to it.
The price for the starter may be fair depending on where it is coming from.
You have to be able to turn the key to the start position before anything happens with the starter.

could be airflow meter fault or throttle potentiometer should see check engine light flashing if either of these sensors are bad, they can effect idle and engine performance.

You have an intermittent problem in your start circuit. I'm sure you also have some choice phrases to describe it, go ahead and vent, we have all encountered frustrating problems.
The reason shops can't find it is because it isn't happening when they look at it. Anytime a hot engine is shut down a lot of heat is generated in the engine compartment. So opening the hood helps yours cool down faster and start quicker, a good clue. I believe if you had it at a shop when it won't start, they might find it. First thing they would check, or you could if you have a voltmeter or testlight, is if power is reaching the starter from the ignition switch in cranking position. This is the small wire on the starter solenoid. If there is power there when the engine won't crank, quickly reconnect the wire and verify if car will crank or not. If still nothing, it may be a poor ground wire(battery or engine ground) or a poor battery cable, since you know the starter is good. If you reconnect the wire and it suddenly starts working, it may have just been a loose connection on the wire you pulled off. If it keeps happening when your hot engine is shut off, test may have been invalid-intermittent problem has only now come back, so run the same test again.
If you or a tech ever find no power on the solenoid wire in START, that narrows it down to the path from the ignition switch to the starter solenoid. One needs to trace that path, looking for where the power is stopped. A couple of possibilities are the starter relay and the neutral safety switch. You could try a new inexpensive starter relay and see if that solves it. If not, then further testing needs to be done before giving up or throwing some expensive parts in and hoping. But you have narrowed it down which helps. It could be some arcane problem like a ground source for the starter relay, or who knows what. Have the start circuit checked, and it would be easier if the no crank condition is present when checked. Good luck.

I had a Nissan doing this to me a little while ago, but couldn't figure out the problem. A couple weeks later, the lady told me she took the car to a shop and they replaced the crank and cam sensors. My bet is that it was the crank sensor.

check the starter relay first please rate -jeff