Your car quietly tells you when something is wrong — through fuel consumption. A tank that used to last 600 km now runs dry at 540. That 10% jump rarely shows up in one refuel, which is exactly why people miss it. Tracked over time, it becomes obvious.
What a rising consumption number usually means
- Underinflated tyres — the most common and cheapest fix; a few PSI low can add several percent.
- Dirty air filter or clogged injectors — the engine works harder for the same distance.
- Failing oxygen/MAF sensor — the fuel mix drifts rich without any warning light at first.
- Habits and conditions — winter cold, short trips, roof boxes and aggressive driving all count too.
The point isn't to diagnose from the number alone — it's to notice the trend early, while the fix is still small.
Let the log do the maths
You can't eyeball this. Consumption is litres divided by distance since your last fill, and distance comes from your odometer. FinMan does both for you: each time you record a refuel with litres and a mileage reading, it computes consumption and real cost-per-kilometre automatically.
The fastest way to keep it current is the photo flow. Send a photo of your fuel receipt and the dashboard to the Telegram or WhatsApp bot, and AI fills in litres, price, total, station and mileage. No typing at the pump.
Tip: always capture the odometer at the same moment as the refuel. Consumption is only as accurate as the distance between two full tanks — a missed reading breaks the calculation for that interval.
Reading the trend
- Log every refuel — skipping some leaves gaps that hide the pattern.
- Watch several consecutive fills, not one. A single high number can just be a highway-then-city mix.
- If consumption climbs and stays up across three or four tanks, check tyres and filter first.
Because FinMan folds fuel together with repairs, maintenance and other costs into a real cost-per-kilometre, a consumption spike also shows up in your running cost. That's the figure that actually matters when you're deciding whether a fix pays for itself.
If you run more than one vehicle, keep each car separate in FinMan so their consumption trends don't blur together. A well-behaved second car makes an abnormal first car stand out even faster.