Question about Hyundai Motor 2005 XG350

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MPG 16-17, with 93 octane in my Hyundai XG 350 L-WHy?

Poor mileage ever since I bought the car. The salesman promised 27-30 MPG in town. I get 16. 17 with 93 octane. I drive within the speed limit and am cautious. I purchased the car used with about 12000 miles on it.

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  • cb012388 Feb 25, 2009

    not always but often when i first start driving the car,after it has been sitting (5hours) when i step on the gas the car doesn't respond. i take foot off the gas and then it lurchs and then seem to act right



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Incomplete combustion due to ignition problems, poor compression, worn or broken EGR valve, sticking injectors, old O2 sensor, dirty air filter, and just about anything else that affects how well the engine would run. Start with a code scanner to find out if there are any stored fault codes.

Posted on Jun 18, 2008


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