Question about 1991 Cadillac DeVille

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Sudden drop in gas milage from 2o to 13mpg

Changed plugs, air filter, & o2 sensor

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  • Mike Butler
    Mike Butler May 11, 2010

    How does it feel power wise on highway, still go like it always did, or feel like it's holding back a little?

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  • 179 Answers

Old car, when rings begin to wear oil leaks into the combustion chamber burning more oil and reducing mpg try a product called restore and use it at every oil change also make sure you dont have black oil and that you are changing the oil at regular itervels also plugs wires roter cap and fuel filter and air filter are changed any abuse to these areas will reduce engine life i change my 350000 mile car every 500 miles reusing my filter everyother time

Posted on Jun 02, 2009

  • fred syn Jun 02, 2009

    old car, when rings begin to wear oil leaks into the combustion chamber burning more oil and reducing mpg try a product called restore and use it at every oil change also make sure you dont have black oil and that you are changing the oil at regular itervels also plugs wires roter cap and fuel filter and air filter are changed any abuse to these areas will reduce engine life i change my 350000 mile car every 500 miles reusing my filter everyother time

  • fred syn Jun 02, 2009

    old car, when rings begin to wear oil leaks into the combustion chamber burning more oil and reducing mpg try a product called restore and use it at every oil change also make sure you dont have black oil and that you are changing the oil at regular itervels also plugs wires roter cap and fuel filter and air filter are changed any abuse to these areas will reduce engine life i change my 350000 mile car every 500 miles reusing my filter everyother time

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"If this has helped you in any way, please rate this solution"

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