I drive a 04 gmc sierra 1500 5.3. I keep tripping the code P0101 and am thinking I need a new MAFS. It has been poor on gas milage. I have a series 77 K&N cold air intake. My question is do I need a stock sensor or a tuned MAFS. I currently run a superchip tuner also. Came with the truck when I bought it.

 

Get some Maf cleaner and clean the Maf. Autozone sells it. If the k&n uses an oiled filter it can cause Maf issues if its over oiled. I swapped to a dry cone filter on my k&n.

 

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