8 Causes of Poor Gas Mileage

 Gas Pump

With the price of gas rising during the summer travel season most of us a looking to get the best milage possible from our car or truck. Thankfully, it's pretty simple to improve your fuel economy by keeping your car maintained and adjusting your driving style. Here are 8 main causes of poor gas mileage.

1. Low Tire Pressure
Low tire pressure creates rolling resistance, which means your car has to use more energy to move forward. Most of today's cars have a tire pressure monitoring system that warns you when the tire pressure is too low. Because the light may not come on until the pressure is well below the recommended inflation level, we recommend using a high quality tire gauge at least every two weeks to ensure all your tires are at the recommended inflation level recommended by the manufacturer.

2. Driving Style
How you drive your car can have a significant impact on the MPG that you achieve between fill-ups. Accelerating quickly from stoplights, speeding and tailgating so you have to continually break and accelerate will waste many gallons of gas over the course of a year.

3. Bad Wheel Alignment
Those Saint Paul potholes can do real number on your suspension. If you're noticing that your car isn't tracking straight and requires constant steering corrections, you need a wheel alignment. As with low tire pressure, poor alignment creates resistance that makes your engine work harder, reducing gas mileage.

4. Using the Wrong Octane Gas
If your car requires a higher octane fuel, but you're using regular grade gas with a lower octane rating , you could be significantly reducing your milage, and not saving as much as expected.

Octane rating is a measure of a fuel’s ability to resist combustion under pressure. The higher the octane rating, the less prone the engine is to knocking. If your car's owner's manual does not recommend high octane fuel, using premium gas is not going to help your car's fuel economy, or improve its performance.

5. Using Heavy Weight Engine Oil

It's not uncommon for owners of older cars to use a heavy weight engine oil to prevent leaks and reduce lifter noise. Because thicker oil causes more resistance in the internal components of the engine, it can reduce fuel economy. We recommend using the oil recommended in the owner’s manual.

6. Bad Spark Plugs, Ignition Coils or Wires

A poorly performing ignition system can cause incomplete and inconsistent combustion. When a spark plug, plug wire, or ignition coil goes bad, the fuel in one or more cylinders may not combust completely. This unburned gas reduces fuel economy. Signs of ignition system problems can include rough idling, stumbling, or hesitating.

7. Clogged Fuel Injector or Fuel Filter

Fuel injectors are precision valves that provide the correct amount of fuel to the engine with precise timing. If the fuel injector is clogged or defective or the filter filter is obstructed, the fuel system will not be able to provide the optimal amount of fuel when needed. The result is incomplete or inconsistent combustion, which lowers fuel economy.

In some cases the injectors may simply need to be cleaned, which will save you money over replacing each injector.

8. Dirty Air Filter

A clogged air filter will restrict the amount of air that can enter the engine, which makes the engine work harder to maintain the same speed. Inspect your air filter regularly and replace it when it looks excessively dirty.

These are just a few of the things that can reduce fuel economy. With a tune-up from Parkway Auto Care you can keep your car in top condition and ensure it's operating and reliably and efficiently as possible.

Parkway Auto Care
1581 Ford Pky St Paul, MN 55116

Phone: 651.698.3208
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We are a NAPA AutoCare Center in St Paul Minnesota, providing the following services:


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