Question 1

What is a good MPG for a car?

Accepted Answer

For a gasoline car, 25-30 MPG is average, 30-40 MPG is good, and 40+ MPG is excellent. Hybrid vehicles typically achieve 40-60 MPG, while electric vehicles have equivalent ratings of 90-130 MPGe.

Question 2

How do I convert MPG to L/100km?

Accepted Answer

Divide 235.215 by your MPG. For example, 30 MPG = 235.215 / 30 = 7.84 L/100km. Lower L/100km means better efficiency.

Question 3

Why is my actual MPG lower than the EPA rating?

Accepted Answer

EPA ratings are tested under controlled conditions. Real-world driving includes traffic, weather, and driving style variations. City driving typically yields 10-20% lower MPG than highway, and aggressive driving can reduce MPG by 15-30%.

Question 4

Does AC reduce gas mileage?

Accepted Answer

Yes, air conditioning can reduce fuel economy by 5-25%, depending on conditions. At low speeds, opening windows is more efficient. At highway speeds, AC is more efficient than the aerodynamic drag from open windows.

Question 5

How often should I check my gas mileage?

Accepted Answer

Check every few fill-ups to establish a baseline. A sudden drop of more than 10% could indicate issues like under-inflated tires, a dirty air filter, faulty oxygen sensor, or engine problems.

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