Runs for 15, then dies

Heads up to anyone with an automatic transmission. My 91 would run for about 10-15 minutes, then the engine would completely shut down. Turns out that this set up uses whats called a crankcase sensor. I'm not 100% on it's history, but many mechanics have told me that the factory sensor doesn't always last more then 10 years. I assume when it goes bad, it sends false readings and shuts down, maybe by temperature, but I'm not sure. I do know that even if yours is not bad, a very simple preventive swap into a new sensor is a wise choice. Believe me, its a buzz kill when you get stranded, with nothing but a crank. If this does happens, wait 15-20 minutes and it'll start, but you won't get far. The sensor averages for about 30 dollars, and is Very easy to swap. Takes ten minutes. Its held in by one 7 or 8 mm bolt. Its located on the left side of the engine inbetween the firewall and the moter down a little bit. I don't think manual transmissions have this, just automatics. I

that's interesting, the problem sounds a lot like a bad ignition module. I am currently working with a bad ignition module and if it dosent do the trick I'll look to that sensor next.

a crankshaft position sensor(cks) is used on just about every vehicle with electronic fuel injection(efi). it is a magnetic inductive sensor that knows exactly how far the crankshaft is turned. there is another sensor called a camshaft position sensor(cms) which is pretty much the same thing these 2 sensors are syncronized so the computer knows when the compression stroke is because the camshaft only turns one revolution for every 2 of the crankshaft. the cks and cms do what the distributor did in the old days. the crank sensor has a tough life with all the vibrations& heating/cooling which is why it's one of the top causes for intermitant no starts. sorry guys i feel like i'm writing a book here. hope your module gets you back in the drivers seat!!