I want an exam requirement assigned to the ability to be flex tuned. You must score a 90 or above on the test , you pay $100 to take the test and Alex is the proctor 😂

Only watched like 10 of your videos and im hooked...dude seems like a genius who talks to us with common sense...i wish i had him tune my car

So is my file like rare now ?

Pretty well explained explanation. Learned something new definitely neat to know 👍🏼

I had the issue you described about vacuum leaks/unmetered air. I just went back to the stock tune, checked the fuel trims, confirm there’s an issue, fix that vacuum leak, go back to e85. I mainly use the flex tune to put a tank of 93 in every couple months.

Glad i learned all this on Honda stuff back in the day. Put it his way when i was on a boosted setup in my honda that car was on like 23 degrees of timing at 9 psi. if i wasnt on full e85 or on good e85 it would have blown up. So unless your flex sensor pulls timing it could blow stuff up really fast.

I see this problem happen on platforms where people haven’t modified anything else and don’t understand concepts and different ways things are done. If you are well rounded and understand the basics this shouldn’t be difficult for people

Great video as always 💪🏽

Glad I got my flex tune. Works great. I run 93 couple times a year then E85. Nothing else. Always run it almost empty. No issues 🤷‍♂️

I work with the public in a business where federal paperwork is required. They have to present specific documentation to be compliant with federal regulations. It is amazing how many people just don't comprehend very simple rules and instructions. So I totally get where you are coming from.

Very well explained! Nice job!

Even on the GM vehicles they will not instantly adjust the learned E content, even though the sensor could be currently reading 85% E. It still slowly increases the value over time. It takes about 5-10 minutes of run time to fully switch from E10 to E85%. You can speed up the logic by going below a 1/4 tank and filling to full which also resets the knock threshold. That's two good reasons to drive until empty and fill all the way up. After watching this video I think some of your customers must have swapped their brains for a EECV's, drink bud light, and piss into their gas tanks calling it E98.

Must say, didn’t really think of the issue with o2s changing fuel trim on a assumption of having ethanol in the tank when it was a unmetered air leak. Definitely makes sense tho.

Damn! I wanted to put my 2019 5.0 pp1 on e85 flex fuel. Guess I can’t do that! Lol. I thought flex fuel meant that you could just put 91 or e85 whenever you wanted. I was wrong. Great video!!

I mean I didn’t know this. I was curious on how the car knew what fuel it had. And I’m not even tuned yet. But was looking to learn about it before I decided to get a tune. Thx for the info

I've meet a few guys and they said they run strictly E85 and I asked them why not do the flex fuel. They said the place who did their cars didn't do flex fuel tunes anymore but nobody ever explained why. Listening to your explanation and I thought that's was what people were supposed to do. Run through car till empty and then put E85 in it. I was running across people before saying you could mix pumped gas and E85.

I've got a question, typically my fuel rails sit at 130°f or higher, does that indicate a problem? Ice read into how the sensor operates and trying to determine how smooth the fuel pressure fluctuation should be. At idle my pressure desired is 400 and actual is 1000 psi. Upon acceleration there are fluctuations in actual pressure but it varies by about 20 psi. Is this normal?

Good morning my boy calling out of San Diego California subscriber the following you a long time going to make the switch buddy from hemi to maybe a second GEN mustang I’ll here there’s only 91 and mediocre E 85 which I have on my charger once I get my GEN two mustang I always wanted to ask this question what’s better for the engine long lasting and longevity the 85 tune or should I get a 91 tune once I put a couple mods on it

I was looking back on some of your videos when you install that ESS you do injectors to or can you get away without doing then

Both of my daily drivers run gm flex fuel sensors, my 04 gmc Yukon and my k swapped civic. The civic I tuned myself, and when switching from 93 to ethanol it takes 5-10 minutes of driving for the fuel to mix and the ethanol sensor to get an accurate idea of the ethanol content. I’ve ran mixes of 93 all the way up to full e85 and dead consistent afr the whole way. I really don’t get why ford would try to use the o2 sensor as an ethanol content sensor.

Alex, how does ford get around the air leak issue with the factory f150 flex fuel software? Even if they’re not making more power on E it would seem they would still go very rich and not throw a CEL if an air leak developed while running 87.

Everything you said was on point..Most cases e50 would outshine 93oct, unless its mixed with hotdog water!

Can Ford use the in line sensor? I really want flex fuel because of availability.

Lund Racing should only give flex fuel tune to YDBT members 😂

Have you seen the supposed flex fuel sensors for coyote mustangs?

What do you think about the plug in flex fuel kits in the market?

I always used it as a stopgap to get me by till I could fully saturate the fuel system and run the regular E85 file 😂 never dreamed of running it on the flex file

This makes some sense to me in why my GT350 didn’t pick up any mph at the track with just E85, I just started it right before basically going to the line.. and it never learned how much E85 was in it? I run E85R.

I believe PCMTEC is working on releasing a CAN Bus flex fuel system for the coyote using a actual flex sensor which would solve this issue. Because at the end of the day if you have an actual flex sensor running at the fuel lines then you could tune it to run true flex no?

I kinda figured this. in my nguauge I found reading that slowly would read alcohol strategy took a couple minutes to read and lock it . Never pushed it till it locked it

Last I heard, Lund was working with PCMtech to get a sensor-based system out. I've been waiting for this for a while, I'm just assuming now they're gearing up to get that out.

So if you use a flex fuel sensor like the one shown for GM on the Coyote, will Lund do a Flex tune?

E85 isnt readily available near me. When you said E50 i assumed it was 93 and E85 mixed i had no idea you could actually get E50 from the pump.

I put the ethanol sensor on my 6.2L in my naturally aspirated escalade because I was annoyed that they were inferring alcohol content from the o2 sensors lol

just so you know, that isn’t a Coyote only thing and GM did away with the actual flexfuel content sensor after gen3. Gen 4 and later GM flexfuel vehicles use similar logic and have similar problems unless they’ve been modified to run a content sensor. A big issue on the gen4 GM vehicles is the ecu will “hang” on a certain “perceived” percentage and cause fuel economy and drivability issues. I actually flatlined my flexfuel stoich table in my 07 Avalanche for this reason. It kept saying I was at 30% ethanol all the time and it was getting horrible gas milage and black smoking from being rich.

So it is very similar to the adaptive octane logic? Also, what PID would you look at to evaluate the quality of the fuel at a particular fuel station? We don't have a shell where i'm at

Late to this but you are correct, E is blended with raw unleaded gas with no anti-knock additive, its ~85 octane or so. so yes its basically ethanol blended with diarrhea..or "hot dog water" lol. Best blend of E85 would be to get E98 and cut it with 93 down to E98 or E70, or whatever preferred blend people want to run. Im surprised people didnt understand how flex is learned in the Gen 3 pcm and Wideband O2... but then again ive had flex via dedicated sensor in 2003 Evo, virtual flex and later dedicated sensor flex in 2013 PPV. So been on both sides of the fence when it comes to recognizing and understanding the differences with both. Didnt like the virtual flex in the PPV but that might be GM E38 pcm capability in a performance application instead of how it was intended, and not necessarily the concept of virtual flex itself.

That’s one reason on the ST platform it’s highly recommended to install an ethanol content sensor so when your mixing for e50 it’s idiot proof. Doesn’t talk to the PCM but at lest you know your E content is within spec.

This was a great video... I am just starting to learn and get into wanting my GT turned up.. I don't know shit!! But I did know without a fuel rail sensor you needed to run your car out completely before switching over... SMH.. If they say empty your car first, empty your car first!!

Saw this issue with people at the track a lot. Not understanding why they didn’t drop time. Even those of us who understood what you have to do with the fuel mix on a street car was/is difficult going to the track for test/tune or doing hero runs. Most tracks are not around the corner from you. They are hours away. So, trying to decide between running full e85 all the way there (worse mpgs and driveability), stop halfway and switch or try to get to track on 0 miles to go.

Great content

Need to make a flash card for the cluster & behind the fuel door

Thanks

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Damn welp that sucks I was hoping to get a flex tune with my supercharger. Right now I have a lund flex tune on my fbo Mustang and it’s very convenient.

Question. I want to run 91 most of the time, and then on a few occasions I would like to run e85. Then I would like to go from e85 back to 91. Would I be able to do this with a flex fuel tune? From my understanding, when I switch from 91 to e85 I would have to flash the flex fuel tune. Then once the e85 is learned after a day or two, I would have to switch to the e85r tune. Is this correct? And if I wanted to switch from e85 back to 91, would i flash the flex fuel tune, wait a little bit then switch it over to the 91 tune ? SOMEONE PLEASE LET ME KNOW IF THIS IS RIGHT

A lot of GM vehicles use the same logic but using the narrow bands and fuel trims. They just called it virtual flex fuel. Works ok on stock vehicles but is more of a pain in the ass than it is worth when tuning for modifications.

Is there a sampling sensor like the GM unit that can be installed on a coyote? If it exists, has Lund used that system for flex tuning already?

I’m a happy customer of Lund with a fully converted Infiniti Q50 700+hp and spent THOUSANDS On injectors . Love the pos it’s rotting in my garage BUT my 2020 pp1 is tuned on a dedicated e85 and I can say I did it the right way 😂 and it was so simple

I had to explain this to a friend a while back about switching. I was like all they are doing is helping you switch fuels... not a place to stay

where is it possible to buy e50 from a pump?

I love my flex tune!!! I have a 2016 gt350 & purchased a flex tune from Lund back in 2018 maybe? The car had around 20,000 miles. Now has 87k miles and has lived mostly on e85! I dynoed it last summer & the thing made 498whp! Absolutely love the flex! Bring back the flextune!! My son has a 2022 GT & just got a lund tune! He is jelly of my flex!! Lol

The other 15 percent in E85 is 85 octane gasoline. They also mix 10 percent ethanol with the same 85 octane to make 87 octane (regular).

Alex, when filling up and swapping fuel/tunes, is it reasonable to let the car hit 1/8 tank then fill up with the different gas and swap tune?

I only use my flex tune in an emergency when I run out of e85 availability and I’m just trying to get from point A to point B.

Great vid 👍

How much would it affect the fuel pumps when you run it till she is dry?

What’s the stoich on e0? will they adjust if running ethanol free gas?

They need to come up with a reflex box like in the bmw world to make flex fuel logical.

Flex tuning went away shortly before I was able to ask for a flex tune and was very disappointed I couldn't get one... and its because of morons who don't let their PCM adjust to the fuel mixture. Even on a stock tune and you go from 87 to 93, you aren't going to get better performance right away. It. has. to. adjust. We lost a good thing because of idiots.

I miss these informational videos from you. I do not understand how yall would deal with these people on a daily basis though. Unfortunately if i change setups i wont have my flex tune for road trips now. 😢

Does anyone know of any other tuner that offers a flex fuel tune?

Really sucks for those of us who understand. Only reason I haven't gone full e85 yet is because there's only 1 station anywhere near me with it. Oh well.

Could I get one if I asked for one, it’s more of a convenience thing for me when daily driving. I’m not trying to go to “Mexico” on a flex tune and be upset if my car doesn’t pull its hardest

I wonder why GM trucks and Ford coyote trucks get a flex tune from the factory…. Even my Nissan Titan can run on E85 from the factory but the Mustang, and corvette / Camaro etc can’t get a flex tune from the factory. GM 5.3 trucks gain something like 30 crank HP just by running E85. Would be nice to pick up a similar number in a Mustang or Corvette.

What about us that already have the flex tune? Do we get reversions when doing mods?

I love my flex tune to transition on my 19, thank god I’ve been a Lund customer for years lol

I just got my dsx flex fuel sensor for my Chevy SS . Gonna need that YDBT tune for old times sakes 🫡

Dem there corn squeezins had the good ol boys cornfused🤔

I'll be honest, I would have uploaded the flex tune and left it alone. Just seems so convenient if you pump "E85" but get 70%

I have a 2018 mustang GT it’s tune with lund but I want to go back to the stock tune how to do it ?? Thanks

Are you telling me all that hot dog water I've been saving is no good?

1:60 lmao damn that's crazy. I remember my tuner explaining all this to me years ago and I was like ok, makes complete freaking sense. Maybe you guys should've created a generic email that explains EXACTLY what you just said and send that to them when they purchase a flex or E85 tune, hell you could probably do a voice memo and sent it to them so they can understand it more 😂

I was wondering because I never saw the sensor nor a "percentage of ethanol" meter in the gauges. Yeah glad you went away with that.

so let me get this straight. I just bought a s550 with the flex tune and all you have to do is run 93 to almost empty, pump e85 full and let it run for 10 mins. then drive for about 30/40 miles and your all set? I'm glad I watch this video because the guy I bought the car from told me just add it and go. Those, If I have them correct are some of the easiest directions to follow.

It is amazing how peeps don’t get it. I don’t blame you. Lol. Here in AZ, most “E85” is only actually E54-ish. I only have one station with 85% ethanol. The rest…..? 50-60% So I have my 91 tune, an E54 and E85. I never mess with flex or mixing. Just dedicated tunes.

I followed every step of the way. Makes sense that GM is doing things the logical way. I couldn't help wondering why Ford wouldn't copy GM. Then the answer came to me. It's cause Ford's to busy huffing that "Hotdog Water". 😂😂

It’s sooo easy on my Zl1, I can switch from 93 to E85 or a mixture of both and it adjusts itself.

We also need a guage inside the car that will actually tell you the amount of ethanol thats in the pump E85. I mean damn the Mitsubishi Evo guys have it why cant we

I feel your pain. I owned a dyno and shut the shop down due to BS like this. Then they would flame you on the internet not mentioning how much of an idiot they were. I never wrote flex tunes due to this reason. I knew it would end up being an issue.

TLDR: Lund stop flex maps due to owner stupidity. 😩 Cool note. GM uses inline flex kits similar to what Cobb does with fa20dits and Ford uses the o2s as a sniffer to correct stoic tables for an unlearned fuel mixture 🤔

Idk anything about this stuff but to me it just seems common sense that you’d have a 93 tune and an e85 tune but have flex fuel tune as a convenient way to switch back and forth without draining the tank lol

💪 tune!

I bought a dedicated E30 tune for my ecoboost, bought three 5 Gal race jugs and beaker test kit, doing math and calculations, etc, never knowing exactly what the ethanol content was, couldn’t fill up my tank, etc etc…. Not only was it super annoying and stressed me out wondering if my shit was gonna blow up. I think I did that for a month before I just went back to my 93 tune lol

Laughs in P59 controller with 3 bar, flex and 4l80 control.

I’m whipped on my 10R80 stang here in Aus. Only thing stopping me from going e85 is that my tuner advocates flex tunes. Regardless of where the sensor is located my worry is “what happens if the sensor malfunctions”? I’ll only go e85 if I can have a designated e85 tune and a designated 93 tune. People laugh at me me because I’ve over built the car (drive shafts half shafts coolers chillers wavectrack diff, billet opg and cs etc) and only putting out 660whp but I just don’t want it to break when I roll race every 6 weeks at a designated track lol

You need to draw it with edible crayons.

Let’s get it

Part of selling services means explaining it properly to the customer so they know what they are buying. I haven’t met someone with this confusion maybe it’s a mustang thing lol

time for a Haltech management

Hey Alex I’m currently getting tuned by lund with john currently but I’m having issues with him and my friend has had issues with him in the past too and switched with you and you got them right, is there anyway I can switch with you I can pay a fee or anything. Pls and thank you!

Basically your saying everybody is dumb now. Agreed. I did 50 hours of research before I went e85. If it’s not oem pay attention!

or get a return line and put a 30$ gm eth sensor on it and run it to a guage... my return line mixed the fuel at idle and i know if my mix is the same thanks to my ethonal sensor readout... then again some people cant change there own oil so its a lot to ask from the unskilled owners out there...

E-85 "test tube" testers are not exactly accurate either. E-85 is a mixture of... Ethanol, Gasoline and HYDROCARBONS. Many of times pump E-85 is actually 70% Ethanol, 15% Gasoline, and 15% hydrocarbon products such as additives, stabalizers, anti-foaming agents. Alex, if you are curious once you install your flex fuel sensor in your vette compare ethanol tests from pump E-85 in a test tube and versus your vettes ethanol sensor. I noticed that E85 in the "test tube" would read E85 but the sensor would only pick up E-70-75. Hopefully you have better pump E-85 than I do locally.

I mean I followed the instructions in the email and never had a problem with it

Damn they ruined it for the rest of us smh , good video thanks bro

Lmao I just explained this to my buddy that has a flex fuel tune and he said ohh that's how it works 😂

I thought about getting a flex tune but how I have my 19 GT tuned and fuel mileage it’s getting naa. I’ll pass.

Seems simple logic to me I wanted to go to flex tune but now I’ll guess I’ll just stick with a 93 tune 😢

#pcmtec flex fuel sensor ftw!