Question about 1996 GMC Sierra

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Poor fuel mileage

I am seeing very poor fuel mileage. About 6 m/gal. I have removed the cat. converts. There is not engine light. Replace the ignition (plugs, wires, cap, rotor) & replaced the air filter with a cold air kit. Changed the fuel pump & filter. The down side to the truck is that it has 190,000 miles on it but it does not burn any oil.

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  • yadayada
    yadayada May 11, 2010

    why would u remove the converters, they have no effect on fuel mileage and u are violating the law as well as making us breath the dirty fumes from your truck!!!!!

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What kind of exhaust do you got, the converter actually may help get better mileage. scan egr for errors in emmisions, get the timing checked mabe running rich, check pcv valves,test knock sensor, 02 sensor( scan might not pick up) lemme know how it goes

Posted on Mar 07, 2009

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