Rate My Ride — Fuel Cost & Trip Price Calculator

The calculator accounts for the main factors affecting consumption: engine type, combined city/highway cycle, cargo and passenger weight, trailer, and vehicle type. In terms of accuracy it exceeds most online calculators, however a number of factors remain outside the calculation:

• Driving style — aggressive vs. eco driving causes a deviation of ±10–15%.
• Road condition — mountain terrain, unpaved roads, traffic jams increase consumption by 5–10%.
• Air temperature — in winter the engine consumes 5–8% more than in summer.
• Engine wear — the difference between a new and a worn engine is 3–7%.
• Tyre pressure — under-inflated tyres cause an over-consumption of up to 2–4%.

Summary: Calculation accuracy depends on driving style, road condition, and the vehicle's technical state. A deviation from real consumption within the normal range is 10–15%. The result is for informational purposes only.

Aerodynamics is the key factor in fuel consumption on the highway. Air drag force grows proportionally to the square of speed, so at speeds above 110 km/h it becomes the main cause of excess energy consumption.

• Open windows or sunroof: At speeds above 70–80 km/h they create turbulence, increasing consumption by 2–4%.
• Roof rack: An empty rack increases consumption by 5–10%, and with cargo or a bulky box — by 15–20%.
• Non-standard body kit: Decorative spoilers and bonnet deflectors ('bug shields') disturb smooth airflow.
• Dirt and ice: Accumulations of snow and dirt on the bodywork create micro-turbulence, gradually increasing drag.
• Underbody: The absence of standard underbody shields turns it into a 'parachute', impeding smooth airflow.

Tip: Reducing cruising speed from 130 to 110–120 km/h can save more than a litre of fuel per 100 km.

Faults disrupt the mixture formation process, forcing the ECU to supply more fuel to maintain stable operation. This leads to loss of dynamics and increased component wear.

1. Sensors & electronics

• Lambda sensor: A sensor fault leads to an over-rich mixture. Consumption increase up to 15–20%.
• MAF sensor: Incorrect air volume data causes improper injection.
• Coolant temperature sensor: If the sensor reports that the engine is cold, the mixture stays rich even after full warm-up.

2. Fuel system & ignition

• Filters: A clogged air filter 'chokes' the engine, while a dirty fuel filter disrupts rail pressure.
• Spark plugs & coils: Misfires mean a portion of fuel is expelled through the exhaust without doing any useful work.
• Injectors: Leakage or a poor spray pattern reduces combustion efficiency.

3. Valve train & intake

• Catalytic converter / Particulate filter: A clogged element creates back-pressure, making it 'hard for the engine to breathe'.
• Intake seal: Unmetered air leaks (after the flow sensor) distort mixture formation parameters.
• Turbocharger: A drop in boost pressure forces the driver to press the throttle harder to achieve the required torque.

Increasing the vehicle's mass directly loads the engine: the heavier the car, the more energy is needed to overcome inertia during acceleration.

Consumption patterns:

• City cycle: The effect of mass is greatest here. Frequent acceleration–braking cycles require energy to move the extra kilograms. At full load (300–400 kg) consumption can increase by 10–15%.
• Highway: At steady speed the effect of weight decreases, as most energy is spent fighting aerodynamic drag. A noticeable increase in consumption is only observed when climbing hills or overtaking frequently.

The physics:

• Inertia: Accelerating a heavier object requires greater torque, which forces the ECU to enrich the fuel mixture.
• Rolling resistance: Increased mass presses the tyres harder into the road surface, enlarging the contact patch and increasing friction.

Tip: Before a trip with a full load, check tyre pressure — this will reduce rolling resistance and partially offset the extra fuel consumption from the added weight.

Suspension faults and incorrect wheel geometry increase rolling resistance. The engine has to spend additional power simply to 'pull' the vehicle forward.

Main sources of loss:

• Wheel misalignment: The wheels do not roll parallel but 'scrub' at an angle to the road. This sharply increases tyre-to-surface friction and raises consumption by 5–15%.
• Worn wheel bearings: Any resistance to hub rotation requires increased engine torque. A seizing bearing is a direct path to overconsumption.
• Faulty shock absorbers: They disrupt the contact patch with the road. The wheel constantly 'bounces', losing grip and causing micro-wheel-spin during acceleration.
• Play in the suspension: Ball joints and bushings with play make the car's behaviour unstable, forcing the driver to constantly correct the steering and make unnecessary adjustments.

Important: In addition to excess fuel consumption, a faulty suspension leads to uneven tyre wear and critically impairs vehicle handling in emergency situations.

Tyre pressure is one of the simplest and most effective ways to control consumption. Insufficient pressure increases the contact patch, which leads to greater rolling resistance: the engine spends more energy simply to 'turn' the wheels.

How pressure affects consumption:

• Pressure drop: Every 0.5 bar below the norm increases fuel consumption by 3–5%. At critically low pressure, overconsumption can reach 10%.
• The 'pulling' steering effect: If the tyres are inflated unevenly, the car constantly tries to veer to one side, forcing the driver to make unnecessary steering corrections.
• Handling and safety: Under-inflated tyres make the car's steering response 'spongy', and braking distance on wet asphalt increases noticeably.

Optimisation tips:

• Check when cold: Pressure should be measured before starting the trip. After driving, the tyres warm up, the air expands, and readings will be inaccurate.
• Your car's specs: Don't rely on 'universal' figures. Find the manufacturer's sticker on the driver's door pillar or on the inside of the fuel-filler flap.
• Regularity: Check pressure at least once every 2 weeks or before every long journey.