Tracking the gas mileage of your McHenry car is an excellent way to monitor how your engine is running and detect problems.

When you’re ready to drive out of your driveway in McHenry, how do you know there’s a problem with your car? There are a number of clues:

• The car won’t start
• The car runs rough
• There’s a repeated thump as you drive
• There is smoke coming out from under the hood
• There is one of many loud noises coming out from under the hood

There are other indications of a problem with your car. But, sometimes, the problem with your car isn’t that obvious.

If one of the symptoms listed above occurs, you could have a dead battery, an engine problem, a flat tire, a coolant leak, other engine problems or … well the list is long. You probably want to call a trusted auto repair technician in the McHenry area. But what if everything seems fine.

You might notice that the engine light is on. Of course, how many people drive their cars for years and years with the engine light on; they never have trouble, right? Actually, if your engine light is on, you should have the car checked out soon. It could indicate something serious with your car and, if the problem isn’t rectified soon, you could do serious harm to your car’s engine.

Another way to monitor the condition of your car is to track the gas mileage. When you keep track of your gas mileage, and you notice a sudden drop in the gas mileage, there’s a good chance that something is wrong.

Of course, if you left the car idling in the driveway to warm up on colder days this McHenry winter, that would effect your car’s gas mileage. But if the mileage drops without any plausible explanations you can think of, you want to have the car checked out. 

Not only is it a good idea to have the problem fixed, and before the problem can cause further trouble, but you also want to save money on fuel; maximizing your gas mileage will save you money at the pump.

Recently, a driver noticed that the mileage on his diesel Volkswagen dropped from its usual 39-mpg to 26-mpg. That’s a precipitous drop. The driver brought his car in to Performance Unlimited where he learned that a backpressure valve in the exhaust system was sticking. All that was needed was to replace the part.

How to Track your Gas Mileage

To track your gas mileage is fairly simple. You need to keep track of the miles you’ve driven between fill ups and how much gas you used.

The next time you fill up on gas, write down the odometer reading. In the sample chart above, on Jan. 17, it read 75,372. Then, the next time you fill up with gas, write down the new odometer reading. Then subtract the earlier odometer reading from the new reading. This will give you the number of miles you drove between fill ups.

Now take the miles you drove between fill ups and divided by how much fuel you pumped at the time of the second fill up. This will give you your gas mileage.