How does eFlexFuel work?

eFlexFuel controls fuel delivery

The operating principle of eFlexFuel is based on processing the fuel injection signals received from the electronic control unit (ECU) of the car engine. The fuel injection is entirely controlled by the eFlexFuel conversion kit. The vehicles each fuel injector is controlled separately, therefore, eFlexFuel adapts perfectly to different fuel injection schemes.

eFlexFuel working principle

Changing the injector opening time

Since the energy content of E85 fuel is lower than of regular gasoline, more fuel needs to be injected during each injector cycle. Typically, the increase in the amount injected is about 28%. This increase is done by keeping the injectors open for longer time. The increase is adjusted according to the ethanol content. This regulation is done automatically by eFlexFuel.

Adaptive system

The ethanol content is detected with the ethanol sensor which is connected to the fuel line. The detection happens in real time and the device ajusts the fuel injector signals accordingly. Any adjustments are not required because the device operations are automatic. In this way the minimisation of the emissions and engine's functionality, according to the manufacturer's original parameters, can be verified.

Cold start function

eFlexFuel is equipped with an external temperature sensor which regulates the devices operations according to the engine’s temperature. This enables the startup in all weather conditions such as in extremely cold weather. The temperature adaptation is active only during engine start. In cold weather the startup may take a few more attemps compared to startup in warm weather. When the engine warms up such problems will disappear. eFlexFuel has been tested in temperatures as low as -30 °C (-22 °F).

The starting of the vehicle may decline when using only E85 fuel because ethanol conversion vehicles do not have the same technical solutions, such as preheating of the fuel, which newer (2011 and up) flexifuel vehicles have. However, E85 has been optimised to Finish weather conditions so the vehicle will function in cold weather as well. The declined cold start ability mean that instead of one startup you may have to attemtp startup two or three times. Many vehicles, however, start the same way as they do when using gasoline. If the starting of the vehicle declines in cold weather, it can be improved by adding 5-10 percent of gasoline in the tank or by using a

Notice! Declined cold start ability is a result of significantly higher ethanol content of E85. eFlexFuel automatically adds fuel feed linearly to ease the cold start. Problems related to cold start also concern factory-made flexifuel vehicles.

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If you cannot find your vehicle you can leave us a compatibility request. We add vehicles to our database when we are asked for compatibility.

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Our technician will check the compatibility of your vehicle before delivery. We always return your money immediately if eFlexFuel products are not compatible.

Please note:

  • eFlexFuel products are not compatible with Diesel engines.
  • eFlexFuel products are not compatible with direct injection engines like TFSI, TSI, CGI, FSI, GDI, EcoBoost.
  • If you switch eFlexFuel products to another vehicle please contact our support first.