My 1988 Camry won't turn over. Seems to happen when hot. I changed starter thinking it was the problem but problem has reoccurred. The condition happens after it has been driven and it is hot. When I let it sit for a while it starts right up. I have checked the voltage at the starter and there is 12 volts there when the key is turned but the starter will not crank.

Any thoughts?

Do you hear I click when the starter will not turn? If so, you probably have worn starter solenoid contacts. This is a common problem with Toyota (Denso) starters. You can read up on the problem and it's cure in this thread in our FAQ's:

http://www.automotiveforums.com/vbulletin/showthread.php?p=3196086&highlight=starter+contacts#post3196086

Mike