2005 Silverado Duramax. Last month in Waco I lost throttle at a gas station. towed to Chevy Dealer, who replaced EGR Valve. Been runing fine since. Today in Edinburg, the check engine light came on again, running fine, no immediate concern, so I kept driving another 50 miles ot hotel. Shut it off, now it will not start. Rapid fires when attempt to start. Any ideas would be appreciated?