Welcome to the TDR. Your problem is more than likely a throttle position sensor. It would help though to know what gears you have and if you are 12 or 24 valve. You sould also post this same question in the 12 or 24 valve forum, which ever applies to your truck so more people will see it that might be able to help you. Good luck getting this straightened out.
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99 2500 QC 4X4 AUTO SB 24V LARAMIE SLT 3. 5 LSD 285-75-16'S SPA Boost/EGT Rancho 9000's Everything but leather NRA Member Great Lakes TDR Member