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Myths about fuel and vehicle function

Myths about fuel and vehicle function: Can you drive on a half empty tank? Is there really a difference between summer and winter fuels?

Are you afraid that driving on fumes will ruin your engine? Convinced that your odometer’s faulty? We picked some of the most common myths and half-truths about fuels and vehicle function so we can set the record straight.

Myths about fuel and vehicle function

Driving on a low fuel tank ruins the engine

Can driving on “fumes” ruin your engine? Not a chance. The idea that driving on a low tank of fuel destroys the engine is one of the most common myths out there. It originates from the notion that this leads to the suctioning up of dirt and impurities at the bottom of the gas tank.

However, a fuel tank is designed with the suction tube at the lowest possible point. This means that it’s always drawing fuel from the bottom, including any impurities that may be present. This doesn’t lead to engine damage because fuel filters capture these impurities, thus preventing them from reaching the engine at all. Fuel level doesn’t in fact have any effect on engine performance.  

Faulty odometer

Do you think your odometer is crazy because during a trip it jumps around by tens at a time? Could it be faulty? It’s quite unlikely. While the fuel gauge informs a driver about the precise amount of fuel left in the tank, information about the remaining amount of drive time kilometers is calculated by a set of complicated formulas influenced by driving conditions.

When an engine is cold, the odometer shows a significantly lower value than once heated to running temperature. Did you drive at full speed for a bit when all of a sudden the estimated remaining distance dropped by 50 kilometers? Don’t worry, burning that much fuel within a few seconds is impossible.

The remaining distance value doesn’t depend only on long range driving formulas but also on sudden changes in workload. If the driving range drops suddenly, for example while passing, it’ll steadily rise back to a reading that’s very close to the original, upon return to regular speed.

The difference between winter and summer diesel is small

Have you ever wondered about the difference between summer and winter diesel? Though some people might tell you that they’re basically the same, the difference between them is actually quite significant. Combustion engines are more demanding for both manufacturing and vehicle operation itself. The most common problems are either slow starts or no starts at all.

This problem occurs during winter months in vehicles filled with summer diesel. The reason lies in the fuel filterability, which regulates the temperature at which paraffin crystals begin forming. This is referred to as Cloud Point. The Cloud Point in summer diesel is surprisingly low, with paraffin formation starting from -6 to -8 °C. As a result, fuel begins to congeal.

The “frozen diesel”, as this phenomenon is commonly referred to, then clogs the fuel filter and prevents fuel from entering the system. When using Verva Diesel, you will be able to start your engine without problems in temperatures up to -26°C.

You can tank only as much fuel as stated in the car manual

Have you ever filled up your tank with more than the maximum amount of fuel stated in your car manual? It can happen. The driver may then get the impression that the fuel station is trying to deceive them or has a badly calibrated fuel stand. The reality is often different. A fuel nozzle contains a gauge inside that is calibrated by the original manufacturer. At Benzina fuel stations, calibration accuracy is tested every two years by the Czech Metrology Institute (ČMI).

The fuel tank size indicated by the manufacturer is in fact just a tentative value and the fuel tank’s real volume is bigger than the one stated in accompanying documents. According to statements made by manufacturers and brand name service stations, the tank volume listed in official documents varies from actual tank volume, including the safety reserve, by up to tens of liters. Because fuel can expand in response to high temperatures, a safety reserve is a necessity.

Should you find yourself in such a situation, don’t hesitate to inform gas station personnel about the incongruity. However, if the station periodically gets their fuel stands calibrated, you can feel confident in knowing that you’re not paying extra for something you did not receive.