Using lots of gas
Take it in to have the engine gone over, and a tune-up. Tire pressure affects gas mileage, air filter, fuel filter, etc.
You may also consider getting the computer system live scanned, it is possible that you may have some sensors that are misreading and that is causing the fuel mixture to swing rich.
Is the check engine light lit? If so get it scanned. Old tired O2 sensors can cause poor fuel mileage.
Check the tire air pressure, drive a little slower. Over sized tires will reduce your mileage.
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