Reset Flex Fuel Alcohol/Ethanol Percentage Level with Bidirectional Scan Tool

Hi all, I have a 2013 5.7 Flex Fuel Crewmax (67,500 miles) and wanted to share that by using a newly purchased 2023 Launch X431 CRP919E bidirectional scan tool, I was able to both read my alcohol percentage level (which was at 85%) and also reset that alcohol percentage level back to zero. This past winter, I started having the hard starting problems due to the high alcohol percentage level issue (the motor incorrectly thinks I'm running E85 ethanol gas but I never have, which causes extended starter motor cranking, an overly rich stumble, and strong fuel smells when it does start). I also had reduced gas mileage overall.

I searched everywhere for a solution and found the TSB to fix it - T-SB-0166-19 (https://static.nhtsa.gov/odi/tsbs/2019/MC-10170730-9999.pdf). Went to the dealer to have them fix per the TSB, but they wanted $1200 and the fuel pump is on long back order. I've also read that some Flex Fuel owners who have had the dealer fix per this TSB have had the same problem return down the road. I needed a solution now and read that resetting the Alcohol Fuel Density level to zero will be a temporary fix (and some report it's a longer-term fix). It seems that some have purchased a Techstream cable with what appears to be unlicensed software (around $40 on Amazon) and tried to reset their Alcohol level using that tool (some with success and others report many headaches/problems with getting that software to work properly - mucho posts about it on ih8mud.com (how to Techstream in 5 minutes is the thread)). Not wanting to spend my precious time trying to get that Techstream software to work, and instead of purchasing a 2 day license from Toyota Techstream (the real version), I decided to find a reasonably priced (to me) bidirectional scan tool that would reset my truck's Alcohol Fuel Density level. I searched and searched, and the only tool I found that said it could do this that wasn't big bucks was the Launch X431 CRP919E (Amazon). I also checked out the XTOOL D7 and D8 scanners but XTOOL wrote me and said those won't reset alcohol levels in the Tundra (maybe they will some day, they look like good tools). Before I purchased the Launch, I wrote the seller on Amazon and asked if the tool would do what I needed and they said it would. Once I received the tool (I've never used a scan tool before), I ran all the updates (you need to do that to get the Special Functions updates you need for Toyota), and then checked my Alcohol Fuel Density Level which read 85%. Seeing it was crazy high and the likely culprit for my problems, I then went into Diagnose, selected Toyota system selection, chose ECM-ECT (engine), selected Special Functions and then selected and ran Fuel Density Learning Value Reset (that will reset your alcohol level to zero - it takes like 3 seconds). My truck now starts right up no problems whatsoever, I get better gas mileage, and it runs smoother (it's noticeably better). I've rechecked my alcohol percentage level since that reset and it remains at zero for now. If I ever have the problem return (I realize it may), I'll just pull out the scan tool and reset the alcohol level (it takes about 2 minutes once you figure out how to find the function in the tool). Anyway, wanted to let you know in case you ever have this problem and you want to get a tool to fix it yourself (and also have a scanner in your garage that can do many other things (e.g., for my wife's BMW (reset this and that)). Hope this helps.

 

Great Info here. Thanks for posting

 

Agreed, thanks for the detailed post with clear directions. Praying my FF doesn't start to have issues.

 

Great post. Thanks!

 

Subscribed just incase my FF does this. Thanks OP!!!

Edit - Feb 2024 my FF is doing this

 

My buddy ‘16 CM with ‘bout 55k started doing this last winter. It’s intermittent though. He also never ran E85. New (1yr old) battery. I send him the TSB and told him to go to the dealer and talk to them tomorrow. He bought the truck and services it at that dealership. So, hopefully he can get some grace out of it and get it looked at and possibly fix before it gets worse. Otherwise, i may pick up this scan tool and do it ourselves.
Thanks OP for the link.

 

There are several on Amazon - is this the one that is about $370 or is it one of the more expensive models?

Thank you so much for sharing this info. The ethanol percentage has been creeping up on my 2019, and I have been researching ways to reset this.

 

It's the LAUNCH X431 CRP919E OBD2 Scanner, 2023 Bidirectional Automotive Scan Tool. It's selling for $372 on Amazon currently (20% off).

 

This is great, thank you!

 

I wonder if my Launch 90 will do it. It’s been a great reader

 

This is an awesome post! Thank you so much. I’m picking one up today in hopes it does exactly what it did for you. Do I need to buy a separate cable or does it come with the unit?

 

The tool comes with the cable so no need to buy a separate one. Good luck.

 

Thank you so much for this post. In 2021 I was having extended crank times on my 18 FF Tundra with 27k miles. Took it to the dealer, had the fuel pump replaced, ECU reprogrammed, and fuel alcohol density reset all under the TSB warranty. Now... ALMOST 3 years later, I'm having the same issue. I called Toyota and they said to bring it in and I would have to leave it with them (booooo!) I've done some digging (to include this post), and I feel very certain I am experiencing the same issue.

My understanding is that the new fuel pumps they are replacing people's trucks with via the warranty, is supposed to have a different/correct sending unit that is more appropriate for the flex fuel system.

I'm hoping the dealer (or myself with this tool you're recommending) can simply reset the level and I'll be good (for how long, who knows)

QUESTION...when you say "I ran all the updates (you need to do that to get the Special Functions updates you need for Toyota)" ----- Are you referencing updates on your truck's ECU? or updates on the Launch ODB scan tool?

Thanks again!!

 

I'm referring to updating the Launch scan tool with their most recent software. Nothing to do with the ECU. Just FYI, so far I've not had to reset the alcohol fuel density since I did that back in April (no start up issues and still have better gas mileage).

 

I just reset mine this evening using the same LAUNCH X431 CRP919E OBD2 Scanner tool. Super easy! My alcohol fuel density was also at 85%. I’ll test out the cold start in the morning to see how it goes.

 

10-4, thanks alot. I’m probably gonna buy the tool.

 

Tested my cold start issue on my Tundra this morning after the reset of my alcohol fuel density last night. Fired right up nice and strong!

 

So glad I found this forum. Just purchased a 2014 Tundra FFV a month ago out of Texas, and this past week it just started this. I have access to an Autel MaxiSys MS908CV. I wonder if it has the capability to reset the fuel trims? If not I reckon I’ll just buy that Launch X431…

 

Can confirm the autel MS908CV was able to do this.

 

I am looking at Launch's website. It wants me to choose between the EU Version or the Global Version. I assume I should choose the Global version. Does your unit indicate if it is EU or Global?

 

I would say global if you’re in the USA.

 

I went with the Global. $387.00 from their website. Amazon prices were around $465.00 now.

 

Thank you for this write up. I bought the same scanner and reset mine today. My reading was 85% as well. My ECU was updated under warranty a while ago and I spoke with the dealer last week because I started having the same issue again. They told me there isn't a new update but did mention the fuel pump change and of course wanted to diagnose it for a fee. For some reason the dealer never mentioned a fuel pump change when my update was completed.

 

Thanks for this write up! My 2013 FFV has been having this issue for the past couple of weeks. I found the Launch scanner at Walmart.com for $372 as opposed to $465 on Amazon. For those that have already done this did you see an increase in gas mileage?

 

Thank you, much appreciated, I purchased the scan tool from Amazon and it should be here Thursday, the last two winters I have fought this. Read several threads saying only fix was to have the ECM reset and a new fuel pump installed, I was not ready to drop $1500 to $2000 only to have to have all this done again in two years. Again thank you for sharing your information, that's what makes this forum a great place to join and hang out

 

How much do dealers typically want to just reset the learning to zero but not replace fuel pump?

Edit: also, just found code for my scangage to read %. It's at 85. Would it run normal if i fill up with e85 at this point or would it still have hard start?

 

Personally, I would never put E85 in my truck. It's JUNK. I would get quote from dealer for reset or buy the scanner off Amazon, use and return it.

 

Well, after resetting my ethanal percentage to zero last night, my truck fired right up this morning, if you are to buy this scanner, make sure you run ALL the updates. I received the scan tool Thursday, proceeded to run the updates and that took around 30 minutes, tucked my scan tool away for the night and got home from work the next day. Took my scan tool out to my truck and started my truck and plugged the scan tool in. Spent 20 minutes and never could find in the menu where to go. Frustrated went back inside and started searching on Launches website, their website was very little help, so started to play around with the scan tool again, low and behold, more updates popped up. 106 updates, these took around 45 minutes to download and install. Went into diagnostic menu and there was the Toyota Lexus menu, went back out to my truck followed OP instructions and reset my percentage. I have always had cheap scan tools, that could read codes and clear codes, but, for the money, this tool is very powerful. I will spend a great deal of time learning how to use the live data, and use all the special functions.

 

According to Launch ( unless they recently changed ) they don’t sell their readers on Amazon. I only know that because I bought a counterfeit one off Amazon. It worked OK for a year, but when I had a problem and called them, they said mine was a counterfeit. I talked to my mechanic buddy and he recommended the TopDon 900Lite bi-directional scanner. Absolutely love it. It even lets you reset the mileage in case you want to change your cluster and the mileage is different. I believe it will even let you program key fobs. My favorite part is its Bluetooth so you can plug in the adapter and take the reader to the engine bay. The reviews were great and they do sell theirs on Amazon.

 

@Danny3737
The seller I found on Amazn claims to be a "legal distributor" for Launch. What seller did you have issue with?