Easy-to-use
Communication was great. Information on products was easy to find on multiple sites
SafetyRey SafetyForce
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eFlexFuel
4.250 reviews
Last reviewed: Feb 20, 2026Do you agree with eFlexFuel's TrustScore? Voice your opinion today and hear what 558 customers have already said.
eflexfuel.comMember since Mar 2026
eFlexFuel is an online company. Based on 50 reviews on TrustPlane, it has an average rating of 4.2 out of 5 stars. Last reviewed February 20, 2026.
Customer Reviews
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50 reviews
91 v e85 = E85 wins
Vehicle: 2005 Toyota Corolla XRS (2ZZ-GE engine, 91octane) I have been running the e-flexpro kit for close to 3 years now. It took some research to put the kit onto the car but nonetheless, i installed it successfully on my first try. Vehicle had to get smogged last year and it passed with flying colors as well (given you plug in the "smog block" provided by company) Spark plugs heat range remains stock @ 6. valves and oil are much cleaner than usual. Gas Mileage difference: 91 averages @ 25mpg. E85 averages @ 19mpg (huge difference i know) with a 13.2 gallon tank i was at the pump OFTEN. i averaged maybe 200 miles p/fill up while 91 averaged 250/fill up. In all for cost savings: (mostly highway driving)$120 = 500 miles on 91 $120 = 750 miles on 85 (more stops at station)is it worth it? you decide. Was it worth it for us? YES. we average 15k-18k miles a year and the savings in gas shows. **remedy to mpg**we blend our mix. i pump 2 gallons of 91 and fill up the tank with 85. Our ethanol percentage remains close to 80% and we now see about 24-26 MPG.
Junior
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Plugged right into my 2015 hellcat
Plugged right into my 2015 dodge challenger hellcat. took about an hour and I used the installation vid to help.
SRT.CURRIE
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Check engine light is on 2022 cadillac escalade
Check engine lights is on they are advertising that no lights on plug and play
harutyun
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Good and bad of exflex fuelOkay here review of E…
Okay here is my one year review of E flex fuels kit overall the kit when it worked is an awesome investment yes, you will see a slight decrease in overall mileage, but that is just due to how much energy ethanol contains the kit lasted me approximately 30,000 miles before the ethanol sensor went bad. The only reason why they are getting three stars and they should get one star, but I’m being generous is when I submitted my warranty claim the company immediately stated that I incorrectly installed the E flex fuel kit and caused the failure. Disregarding the fact that the kit has been in the car for over 30,000 miles. I had seen reviews like this regarding warranties, but thought nothing of it. Once I was accused of causing the failure. I immediately gave up remove the E flex fuel kit from my vehicle and returned it back to its factory settings. Yes, the technology is cool and does save you some money if you’re in a bind the kit overall is awesome but E flex fuels attitude is not so awesome. Immediate blame towards me made me just remove the kit if they would not have blame me for an obvious part failure I would’ve continued to run the kit so overall, yes, the kit does work, but keep in mind failures may occur and E flexible will blame you for the failure. They will not warranty any parts for you. Just keep this in mind. They also deleted my comments on Instagram when I called them out about this issue and if you look into their bad reviews, you will all see the same thing that e flex fuel just blames, whoever installed the kit for their part failures
Casey Aldridge
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Recommended product
All items were delivered quickly and were of excellent quality.
Stempy
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I receive my E flex fuel Pro kit and…
I receive my E flex fuel Pro kit and is the best thing that I’ve ever purchased so much increase on horsepower. I love it. I have a 2021 Dodge charger hellcat redeye and when I tell you, it has a different type of power when you run in that E 85 the only problem I’ve had so far is that it do not let me register my car and when I do Phillips with the E 85 and I’m currently running full E 85 with no check engine light on no nothing straight E 85 and I haven’t had no problems. Another situation I’m having is that the E 85 gas station it’s an hour away but other than that the system Install is straightforward. It’s all common sense and plug-in play. I love it. Thanks you guys.
Carlito
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Honestly Im shocked at how terrible my…
Honestly Im shocked at how terrible my Gas Milage is i barely drove 175 miles on a full 26 gallon tank in the city with an empty truck where i was getting up to 300 miles a tank pulling a 26 foot trailer on regular 87. I feel like recovering my Investment for the Flex kit at $1.50 in savings per gallon is going to take alot more than 20 tanks since ill be at the pump alot more often. And i have not noticed any power gains at all. In my honest opinion.
Julien Durand
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Complete scam ruined my injectors 3…
Complete scam ruined my injectors 3 months later my Computer and Customer Service can care less
Leo Ruiz
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Great product, terrible instructions
The kit is 10/10 and worked flawlessly once installed. The instructions supplied however were lacking and generic. I bought and installed the flex fuel kit in my 2004 BMW 325i. I had to find a different manufacturer to look at their instructions to get it done.
Jeremy Robinson
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I highly recommend Eflexfuel for all…
I highly recommend Eflexfuel for all E85 needs, thanks to their exceptional customer support. Daryll has consistently delivered outstanding support since the outset, responding promptly to my inquiries and resolving a minor issue. His commitment to customer satisfaction is outstanding. After installing the system and switching to E85 in my Challenger, I noticed a significant performance improvement. The difference is substantial, and I regret not making the transition earlier. The switch from 93 to E85 has resulted in considerable benefits, including a cooler burn and engine cleaning. Moreover, filling up with E85 is more cost-effective, at $30 compared to $60-70 for 93. The flexibility to switch fuels for weekends and race days is also a convenient feature. I strongly recommend Eflexfuel to anyone considering the switch. Thanks Eflexfuel !
Travis Lytle
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I have 2013 f150 raptor svt and…
I have 2013 f150 raptor svt and installed the eflex pro kit about a month ago. I’m highly satisfied with the product and the installation process was pretty easy. Surprisingly enough, my gas milage has gone up from 10.5 mpg to 11.3mpg so far. I am also running a more aggressive tune on the truck. I used to pay almost $140 for a full tank as the high compression 6.2l only takes premium. Now with just running e85 I’m only paying $60-80 for a full tank!! The truck does also feel like it has more bottom end power, can’t wait to unlock its full potential by additionally tuning it for e85 and adding a supercharger.
Dominik Pesch
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I installed the Eflex Pro in my 2012…
I installed the Eflex Pro in my 2012 Ram 1500 with a 5.7 Hemi which i just bought as my backup truck to my 1995 Chevy Crew Cab dually with a 6.5 turbodiesel. I bought the Ram with a 5.7 Hemi with the intention to convert to E85 for price economy over diesel. I bought the truck for about half price of a used equivalent diesel truck and near me E85 is selling for $2.599 per gallon while diesel is at $5.299 per gallon. I have not seen any increase in fuel consumption while running E85 but the price of a fill up is about half of normal gasoline or diesel. Sure I get about 3 or 4 mpg less than with diesel buy price at the pump more than makes up that little difference. Best thing i did was to install the eFlex system. I am definitely a satisfied user!!!
William Fassel
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Works great
Works great! I’ve been running E85 in my Toyota RAV4 for two years after it was installed. I’m very satisfied with the results.
Michele S.
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Great customer service I had a small…
Great customer service I had a small issue with reversed polarity and they walked me through it in a snap.
Robert
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Product works although my car has…
Product works although my car has hiccups every now and then when pressing the gas at any percent ironically all of the stores they recommend to get yours installed at charge triple the price I ended up getting mine installed at my local Infiniti dealership for half the price I recommend you look for a great mechanic before you buy this product and don’t bother looking at the ones they refer you to
Alex Perez
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Quality
Bought awhile back, Good kit,but as for as much money I spent tho you’d think the injector shells would be manufactured better. Lock in both wires in connector shell. Verified both wires are locked in and fully seated. Go to plug into vehicles harness and it pushes out the circuits out of the connector shell on y’all’s kit. It’s done it on 5 out of the 8. Pain in the ass
Chris
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When it worked it was great
When it worked it was great. Loss of communiciations with vehicle and also with app when flexfuel module shuts off. All connections were cleaned, grounds checked, cleaned and retorqued as well. Great setup. Had the kit almost a month and issues started. At this point confidence is lost and I requested to return and for a refund.
Michael Rollins
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The ethanol sensor does not fit where…
The ethanol sensor does not fit where instructions said it supposed to be installed.Haven't got a chance to test because off this issue.Theres no info in the internet of how the ethanol sensor is mount/installed on a jeep 2021 3.6 engine
Cristian Bajonero
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So far so good i would definitely…
So far so good i would definitely recommend Device pays itself within 2-3 months
Antonio Tovar
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According to TrustPlane, eFlexFuel has a 4.2/5 rating based on 50 verified reviews as of April 2026. Source: trustplane.app/company/eflexfuel-com