5.3 Liter Intermittent Stalling Problems

[Rotarydave]

Hello, this is my first post on here. I'm working on a friend's 2000 Chevy Silverado 1500 with the 5.3 liter V8. The problem is that it intermittently stalls out while decelerating or idling when the engine is warm. Sometimes, it'll stall out and die after 15 minutes or sometimes an hour. Seems like it only happens when it is warm outside or I'm running the motor hard. Sometimes, it will start back up after a few minutes or it won't restart until it cools down. There aren't any DTC codes that a stored or present. The fuel pressure is good as with the fuel pressure regulator(I also checked when the engine wouldn't start). I cleaned the throttle body, IAC valve, MAF sensor, and replaced the PCV valve, fuel filter, and spark plugs. Is it possibly the crank positioning sensor malfunctioning as with the 8.1 liter engine?

 

Any suggestions or tips will be greatly appreciated,

David Hosey

[Rotarydave]

Or water in the fuel tank?

[Rotarydave]

It was the crankshaft positioning sensor! I love it when a $50 dollar part causes so much frustration!