The car is a '96 Camry LE (5S-FE).
Earlier today I was coasting down a mountain, going about 50 mph, when the tachometer started rapidly dropping up and down. It continued to coast for a minute or so until the engine light came on and car died completely. I pulled off of the road and let the car cool down for about 15 minutes. It started up and ran fine for a few minutes, but the tach soon started jerking up and down. It ran steadily as long as I kept my foot on the accelerator, so I continued driving this way into the next town to look for an OBDII scanner . . . but I didn't find one. So I made a (stupid) attempt to continue to the next town, but only made it a few miles before the engine speed became really erratic and the car died again . . .
Now it doesn't start at all. The starter will crank the flywheel all day, but the engine won't run. I had it towed and was able to find a code reader - it's showing a problem with the crankshaft position sensor. I'm going to throw in a new sensor tomorrow . . . Does this sound like the source of all of my problems? I would really appreciate any suggestions!