After a mere 190,000 miles on my '90 Camry V6 the thing quit on me on the way to work. Wouldn't restart for anything; just died on me going up a hill. Left me and two others out in the cold rain. At least it went out near the shoulder so I didn't block traffic. Had the car towed to my mechanic, who kept it overnight and couldn't find anything wrong. I drove the car home, and a day later it cut out on me again.
I searched under the hood for anything unusual, and I spotted a bell wire coming from a connector obviously chewed in half. I connected it using a jumper, and I haven't had the problem since. The reason I think it was squirrels is because I saw my ignition wires nibbled a few weeks earlier and I replaced them.
So, beware of them critters! They'll do-in a Camry!