Although your car is usually good on gas, you may have noticed lately that the time in between fill-ups is shorter. This is especially true when you have not altered your daily routes or driven any further than usual.
If you have noticed that your car's gas mileage is suddenly bad, there is most likely an issue with the engine. There are a couple of possible components in the motor that can adversely affect your vehicle's fuel economy which will need to be addressed by an auto mechanic.
1. Spark Plug Ends Are Worn or Corroded
One possible reason why your car's fuel economy has decreased significantly is that there is an issue with the spark plug ends. The spark plugs are what ignite the gas within the combustion chamber to allow the engine to run. Over time, the ends of the spark plugs can become worn down or even corroded. The corrosion can come from excessive carbon buildup on the ends or exposure to too much moisture.
If the ends of the spark plugs are no longer clear and/or in good condition, they will not be able to fully ignite the fuel. When this happens, the engine senses that it needs more fuel and will continue delivering more gas even though it is not combusting completely. The plug will need to be replaced and properly gapped for your car's particular motor to help the gas mileage.
2. Oxygen Sensor Has Started to Fail
Another component of the engine that can contribute to poor gas mileage if it starts to fail is the oxygen sensor. This part of the motor delivers the correct amount of air to the combustion chamber, allowing the ignited fuel to burn more efficiently and cleanly. If not enough air is mixed with the fuel, the gas will not ignite properly, leading to less power and poor fuel efficiency. When the oxygen sensor is to blame for the issue, it will need to be replaced by a professional.
Whether your car's recent decline in gas mileage is caused by bad spark plugs or a failing oxygen sensor, the vehicle's fuel economy will only get worse if something is not done about it. Take your car to a shop that offers auto repair services to have them diagnose the actual cause of the poor mileage so that the appropriate action can be taken to fix any issues that they may find.