I would check #8 plug wire. You can check the plug wire with a digital meter to see if its good, or just move it to another cylinder to see if the problem follows if you dont have a meter.
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1999 Z28 Camaro|Cut up
2003 CC Duramax Dually|19.5 w/245/70/19.5|5in exhaust
2009 G8 GT 408hp/402tq sae|Rotofab CAI|LS9 Cam|Headers|GXP Mufflers|Custom System
2009 Tahoe stock
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