Wrong tire pressure is one of the most overlooked fuel guzzlers. Just 0.3 bar too low increases fuel consumption by 1–2% per 0.1 bar. A regular check takes 5 minutes and saves €50–60/year.
Step by step
Low tire pressure enlarges the tire's contact area, this increases rolling resistance. Your engine has to work harder to move the car. A tire with too much pressure sits tighter and rolls easier, but reduces grip. Optimal is: +0.2 bar above manufacturer specs (listed on your driver's door or manual). This is the sweet spot for fuel consumption and safety.
Source: ADAC Tire Pressure Study, ADAC: up to 6% increased consumption with low tire pressure; optimal is manufacturer specs +0.2 bar
Step by step
- Find Your Target PressureOpen the driver's door. Inside the door frame or on the fuel cap, you'll find a sticker with the target pressure (e.g., 2.2 bar front, 2.5 bar rear). Add +0.2 bar for fuel optimization.
- Measure Cold PressureMeasure tire pressure in the morning or after at least 3 hours parked. After driving, pressure is warmer and higher from friction, this skews the result.
- Check All Four TiresUse a digital pressure gauge (~€15). Check all four tires. Reminder: don't forget the spare if you use it regularly.
- Check MonthlySet a calendar reminder. Pressure naturally drops ~0.1 bar per month. Temperature swings make it drop faster.
- Check Valve SealsIf pressure keeps dropping, the valve might leak. Have it checked at a gas station or shop (usually free).
Worked example
Before: Martin drives with original manufacturer specs: 2.0 bar, averaging 7.8 L/100km, 1,500 km/month = €182.50
After: After raising to 2.2 bar: 7.3 L/100km (-6.4%), 1,500 km/month = €171. Savings €138/year