What causes a sudden drop in fuel efficiency?
If the CEL is on have the codes checked and it will probably lead you to your problem. Such a drastic drop in mileage is often associated with a bad 02 sensor. I’ve had them go bad and cause a 25-35% drop in fuel efficiency. keith July 6, 2016, 2:38am #4 Did you have anything done to the car just before the mileage dropped?
Why does my gas mileage drop after an oil change?
Before an oil change, always make sure that you get the right viscosity for your vehicle. Most vehicle owner’s manuals state exactly what type of oil to use for optimum mileage, with names like 10W-30 or 5W-30. If you get the wrong oil you may notice a drop in mpg and overall poor performance, especially in extreme heat or cold.
What to do if your gas mileage goes down?
If you notice a sudden drop in miles per gallon (mpg), don’t run straight to a mechanic. Instead, check on these common reasons for a sudden mileage decrease that you may be able to fix yourself.
What does it mean when Your MPG drops 20%?
BTW, there is a code if the ECT (engine coolant temp) does not come up withing a certain time frame. You could also have a fuel leak. My 2010 FIT dropped 20% immediately upon moving to a much colder climate. I checked tire pressure and changed air filter, changed gas stations. Still off by 20% ( 10 miles per gallon).
Before an oil change, always make sure that you get the right viscosity for your vehicle. Most vehicle owner’s manuals state exactly what type of oil to use for optimum mileage, with names like 10W-30 or 5W-30. If you get the wrong oil you may notice a drop in mpg and overall poor performance, especially in extreme heat or cold.
If the CEL is on have the codes checked and it will probably lead you to your problem. Such a drastic drop in mileage is often associated with a bad 02 sensor. I’ve had them go bad and cause a 25-35% drop in fuel efficiency. keith July 6, 2016, 2:38am #4 Did you have anything done to the car just before the mileage dropped?
What can I do about poor fuel economy?
So, knowing the common causes, of poor fuel economy, is just the tip of the iceberg. It may not seem like that big a deal but, staying on top of oil changes; replacing the air filters when necessary and throwing some; fuel-system cleaner in the tank every now and then can go a long way; in keeping your engine running the way it should.
What to do when your gas mileage goes down?
If you’re experiencing reduced gas mileage, there are a couple of things you can do to minimize fuel waste. Your driving habits play a large role in the mileage of your car. By making some changes to how you operate your vehicle, you may be able to achieve better gas mileage.