WIthout actually seeing the car and its computer readings its pretty tough to diagnose this - I can give you generalities .. The fuel system is controlled by a few sensors / O2 ( Oxygen sensor) / Manifold ( Map) sensor / TPS ( Throttle Position ) sensor / MAF ( Air Flow meter if it has one ) all which can effect fuel economy. Is the check engine light on - If so the diagnosis for a Local technician should be easy. If not it is a little more difficult but can be found. Good luck
Has your driving style changed, I.E., a little heavier right foot? Check the tire's air pressure and make sure they are up to what is specified on the door placard or owner's manual. Make sure the tires are properly aligned. Replace the air filter. Cheap but good: Purolator, not cheap but best: K&N. Change the fuel filter. Is there a leak somewhere in the fuel system? Could a neighbor with a hose be helping himself to free gas? Let us know what the problem was and how it was fixed.
whats with people responding to questions that were posted over 2 years ago...look at the dates before you dig up an old post that they will never read
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