Q: Car getting low gas mileage

asked by on August 09, 2016

Going to work round trip, I have to drive all the way on the highway for 46 miles. I go around 13 miles at 70 mph and at 55 mph I go about 10 miles. My car, recently purchased used, has approx. 92,000 miles. It was previously owned by a rental company and recently had been turned in. The gas gauge is moving very quickly. Perhaps it is reading correctly and I'm just not accustomed to it, but I think I’m using at least nearly a quarter of a tank of gas to go these 46 miles. That calculates to about 250 miles per tank. That is only 16 mpg with my 15-gallon gas tank. I read that this car is 25 mpg highway and 18 mpg city, with a combined average of 20 mpg. I'm very puzzled why I'm getting such bad gas mileage. Should I change the air filter or what can I do to fix my vehicle?

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Yes, 16 mpg is very low for a Kia Rondo, especially with the amount of highway driving you do daily. Start with basics like the air filter and tire pressure, which are two big items that will rob you of fuel economy.

The parking brake adjustment should be checked as a dragging parking brake which will kill gas mileage. One last thing to look at would be having the faults read out of the engine computer.

If there are faults preventing the computer from going into an open loop operation, the engine computer might stay in a preprogrammed closed loop and not meter the fuel as efficiently as it could for driving conditions. You may want to enlist the help of a mechanic, such as one from YourMechanic, who will have the expertise to examine the decreased gas mileage that the vehicle is exhibiting and recommend corrections to get the fuel economy back where it belongs.

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