Frequently asked questions

eFlexFuel E85 flex fuel conversion kits are fully automatic bolt on kits that do not require tuning or any other modifications. eFlexFuel Technology ensures that the engine is always running optimally whether you’re using E85, gas or any blend of ethanol and gas. This means maximal power and torque but also minimal fuel consumption and emissions. eFlexFuel kits are compatible with most gasoline and hybrid cars, trucks, SUVs, motorbikes and powersport vehicles.

All eFlexFuel kits come with an eFlexApp smartphone application, while eFlexPlus and eFlexPro kits also connect to an eFlexTuner Windows software that comes with a wide range of engine optimization features including the capability to make your own custom tunes. The use of eFlexApp or eFlexTuner is optional and all eFlexFuel kits work fully automatically without any tuning.

By using E85 with eFlexFuel you can increase your engine performance by up to 15%, while saving money at the pump and emitting less harmful emissions.

Check out the pricing for eFlexFuel for cars, trucks and SUVs and for eFlexMoto for motorbikes and powersports vehicles. The price of the products is the same for any compatible vehicle.

Yes, most likely. eFlexFuel kits are compatible with most gasoline and hybrid vehicles on the road. You can verify your vehicle compatibility from the eFlexFuel compatibility engine. If your vehicle is missing, please make a request and our engineer will verify its compatibility and notify you via email.

We always make sure to deliver a complete kit that is specific to your vehicle. So, when you are making the purchase please provide us with your vehicle make, model and year, along with the registration number for verification purposes.

Remember that your vehicle needs to be adequately maintained and in normal working condition.

eFlexFuel products are not compatible with the following: direct injected engines (coming in late 2021), diesel engines, carbureted engines or engines with mechanical fuel injection.

Yes. All eFlexFuel products are fully automatic flex fuel systems. You can fill up with E85, gas or both. eFlexFuel Technology will automatically adjust the engine to run optimally on any fuel blend.

E85 always has above 100 octanes making it the most potent fuel available at the pump today. The power gains with eFlexFuel and E85 vary from 1% to 15%, depending on the vehicle. In naturally aspirated engines and hybrids, the power gains are very moderate. But with forced induction engines, you can expect to see up to 15% gains with eFlexPro that features thorough fueling optimization capabilities on eFlexTuner Windows software for professional use.

As a rule of thumb, the more performance your engine has, the more you will gain with eFlexFuel and E85.

Read more about the performance of E85 fuel and view example dyno graphs

Yes. If you have experience in simple automotive maintenance and repairs, you will most likely be able to install eFlexFuel products. DIY installation usually takes 2-3 hours and only requires a few basic tools and a multimeter. eFlexFuel is delivered with a general installation manual. You can also find installation videos on our YouTube channel. Our customer service can be reached by phone, if needed.

Optionally, you can take your vehicle for installation by a professional and expect to be charged for 2-3 hours of work.

Yes. When eFlexFuel is installed, no permanent changes are made. Removal of the system is fairly easy. Furthermore, we can provide a bypass module for short-term use.

No. But if you would like to make a custom E85 tune, eFlexPlus and eFlexPro products come with capabilities to make your own tunes with eFlexTuner Windows software. You can switch the tunes on the go with the eFlexApp smartphone application.

Yes. A modified engine, eFlexFuel and E85 fuel are a perfect combination. E85 has always above 100 octanes which maximizes the power gains from the modifications. Furthermore, eFlexPlus and eFlexPro products are specifically designed for performance and come with a range of engine optimization capabilities with eFlexApp smartphone application and eFlexTuner Windows software.

If you have a modified engine, please let us know what kind of mods you have so we can confirm the compatibility for eFlexFuel and E85.

No, not in most cases. We always verify the compatibility of your vehicle with eFlexFuel and E85 and our compatibility engine contains verified compatibilities for thousands of vehicles. If your vehicle needs any other upgrades, other than eFlexFuel, to run E85, our compatibility engine contains that information and we will let you know. In this case, you can decide whether you would like to purchase eFlexFuel or not.

No. Your vehicle’s performance and durability are of great concern for us. That is why eFlexFuel is designed to make sure that the engine is always running optimally and there is no risk of engine damage.

Furthermore, for every purchase, we make sure that the vehicle is compatible with eFlexFuel and E85. Our engineers verify, for example, the fuel pump, fuel injectors and fuel lines. If there are any compatibility or durability concerns, we will let you know.

No. eFlexFuel system won't compromise the durability of your vehicle and the system itself is completely service free and designed to last the lifetime of the vehicle.

Furthermore, you do not need to service your vehicle or change the oil more frequently. Still, as your vehicle’s optimal performance and durability are of great concern for us, we recommend shortening the oil change intervals, especially if the manufacturer’s recommendation is over 10,000 miles.

On average, you can expect to lose 15% - 30% of MPG with full E85. The loss in miles per gallon is related to the ethanol content in E85 that can be anything between 51% to 83%. More ethanol in the fuel means less MPG. Other things that affect the consumption are the vehicle, the driving behavior and the driving environment.

It is important to note that E85 is usually significantly cheaper than gas and this price difference makes up for the loss in MPG. Furthermore, as E85 always has over 100 octanes, the right price comparison would be Premium or Supreme.

If you are mostly concerned about saving money at the pump, you can fill up with a blend of gasoline and E85. With lower ethanol contents (for example 40% to 50%), the loss in MPG is often hardly noticeable but you will save at the pump thanks to the lower price of E85.

Yes. But in cold temperatures (less than 35°F) we recommend taking the following steps: Use an engine block heater, whenever possible. Fill up with some gasoline (10% or more) to lower the ethanol content. Make sure that the engine is well maintained and, in particular, the ignition components and spark plugs are in normal working condition.

eFlexPlus and eFlexPro come with an adjustable cold start feature that is accessible from the eFlexApp smartphone application or eFlexTuner Windows software. This will allow you to configure the cold start specifically for your vehicle, if needed.

Yes. In fact, as E85 burns cleaner and contains less harmful aromatic compounds, the results in a smog test will be cleaner than with gas. Also, you can still use gas for the smog test which will produce exactly the same results as without the eFlexFuel kit.

We are currently working on CARB and EPA approvals for eFlexFuel kits. For now, all eFlexFuel products are strictly for off-road or racing use only.

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