Replaced the throttle return spring. It's been 10 or 11 years since I replaced it, and I thought it was about due. About 2 years after I purchased my truck, I came out one morning to start the truck, I hit the starter button and it went wide open. I killed the engine, then put my foot on the accelerator pedal and it was flat against the floor. I raised the hood and looked at the throttle linkage, and there was the throttle return spring hanging by one end, the other end had broken off. This happened while the truck was just sitting parked and not running. Next time you have the hood up on your truck, take a look at your throttle return spring, probably one of the easiest things to do, and look for wear or rust on the hook ends. Thankfully this didn't happen while I was running in traffic!