Having problems with your 2003 GMC Sierra ?
My 2003 gmc sierra loses power sometimes. the truck seems fine when in park or neutral but doesn't want to move in drive(lack of power, have to put accelerator to floor to get truck to move). it seems to be flooding with gas because exhaust smells like gas and it burns way more gas than normal. seems to work better with little gas in tank. I have changed fule pump, fuel filter, and plugs, makes no difference
Repair Help & Product Troubleshooting for 2003 GMC Sierra
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