When you notice you are filling up more often for the same kilometers, that is not a coincidence. Increased fuel consumption is always a symptom of something. Sometimes the cause is trivial, sometimes it points to a more serious problem.
Spark Plugs - Small Part, Big Impact
Worn spark plugs do not ignite fuel efficiently. Some fuel passes through unburned, the engine runs worse, and consumption goes up. Spark plugs should be replaced every 30,000 to 60,000 kilometers depending on the type. In our experience, people often forget about them because the car "runs fine," when in reality it is burning 10 to 15 percent more fuel than it should.
On LPG it matters even more: LPG requires a stronger spark than gasoline. Worn plugs on a car with an LPG system cause bigger problems than on straight gasoline. We recommend iridium spark plugs for LPG vehicles.
Clogged Filters
A clogged air filter or fuel filter forces the engine to work harder. An engine that cannot breathe properly burns more fuel. Check the air filter visually. If it is black and full of dust, replace it. It costs very little, and the difference in consumption can be noticeable.
Oxygen Sensor (Lambda Probe)
The oxygen sensor measures the amount of oxygen in the exhaust gases and helps the computer adjust the fuel mixture. When it weakens or fails, the mixture is often too rich, meaning the engine burns more fuel than necessary.
How to spot it: Usually the check engine light comes on. Consumption can jump by 20 to 25 percent. The oxygen sensor has a limited lifespan, typically 100,000 to 150,000 kilometers. If your car has that kind of mileage, it is worth checking.
Tire Pressure
This is the simplest thing on the list, and many people ignore it. Tires below the recommended pressure create more rolling resistance. Just 0.5 bar less on all four tires can increase consumption by 3 to 5 percent.
Tip: Check pressure at least once a month, always on cold tires. The recommended pressure is on the sticker on the driver's door or in the owner's manual.
Driving Habits
We are not here to tell you how to drive, but here are the facts: hard acceleration and late braking burn significantly more fuel. Driving around town at high revs, only shifting at 4,000 to 5,000 RPM, constant braking then accelerating, all of that eats through fuel.
A real example: A driver who drives smoothly on the same route can use up to 2 liters less per 100 km than an aggressive driver. Over a month, that is a meaningful difference.
Air Conditioning
The A/C puts load on the engine and increases consumption, usually by 0.5 to 1.5 liters per 100 km depending on the engine and temperature. That is normal. But if the A/C seems to cost more than that, the system might be low on refrigerant or the compressor might be working harder than it should.
When to Start Worrying
If consumption has gone up by more than 15 to 20 percent with no change in driving habits, that is a signal to run diagnostics. Especially if the increased consumption comes with any of the following: power loss, rough engine idle, check engine light, or an unusual smell from the exhaust.
What You Can Do Yourself
Check your tire pressure, look up when the spark plugs and filters were last changed, and pay attention to how you drive. If that does not help, stop by for diagnostics and we will find the cause quickly.