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Q: Bad gas mileage

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My truck has been getting low gas mileage lately. About a year ago, it was around 15 MPG and now it dropped to 8 MPG. I understand that it is a truck and needs a lot of gas, but this is very poor gas mileage. I've done some checkups and everything seems fine. The catalytic converter is ruled out as a cause. I had the intake cleaned; spark plugs replaced; wires checked; new air filter installed; switched to Shell gas. What could be causing such bad gas mileage?

Hello there. A decrease in fuel milage can be attributed to a few different faults. The most common causes are leaking fuel injectors, oxygen sensors, coolant temperature sensors, vacuum leaks or exhaust leaks. A qualified technician, such as one from YourMechanic, will check all of these for proper operation and can make any repairs required.

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