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

Looks like once a year or so.

 

I’ve had to do it twice. First time in 2022. Again this winter.

There is a working theory the health of your O2 sensors will determine reset frequency as they are what is used to calc the alcohol percentage.

 

has any one replaced o2 sensors to try?

 

Returned the Launch tool and bought the D7. I like a bigger display and the ability to program keys.

 

Just got my launch tool how did you guys get to that setting to reset the ethanol density? Can’t find it

 

I think this one worked for me:

Diagnostic > Automatically Search >System Sclection > Selcet "ECMECT(Engine and ECT)" System > Special Functions > Fuel Density Learning Value Reset

The software has to run its updates before using the Launch.

 

@Dkheaddo helped me out with this too. Here's what we did to see the current values (you'll want to know what you're at before you clear):

Diagnostic, 16pin, System, powertrain, ecmect, read data stream, check these boxes - alcohol density estimate, long FT #1 & #2, click ok and it’ll split screen all three

 

Does anyone else (FFV only) with the D7 see "Ethanol" where it states your fuel type?

 

My Launch came in today, picked it up for $112 delivered on Ebay. It showed I had a P1604 stored in the ECM which I didn't know about. I am not having any starting issues, but my fuel mileage blows (big tires probably) and my idle isn't perfect. LT fuel trims were 9/10% and alcohol density estimate was 0%, weird. Cleared it all out, we will see how it goes. I was a little worried about this one as it came from Ebay, but looks identical to the other pictured with a different serial number on the box.

 

Looks legit. Ever since I reset my trim levels, my truck's been running smoother and, seemingly, quicker... I hammer down and I swear it scoots better than before.

 

I definitely noticed an improvement with how the truck runs, surprised about that one.

 

Bought the XTOOL D7, super easy to use. 170+ updates was a pain. Connects and works fast. Engine noticeably noisier initially.(Injectors?)
Took it on a 15 mile run with 2nd tank of non ethenol fuel and reading remained at "0". Best economy I have seen. (16-17) cruising on flat at 55. Yes, it will go down commuting.
Stared at the tool for about 3 days wondering if it would work but it was a non event.
My reading was 18% with non ethenol fuel.

Thank you to everyone in this thread.

 

Has anyone bought a non FlexFuel ECU from eBay and tried it?
They are only $100-ish used.

I "assume" it would not work without some programming help but wanted to ask.

 

D7S on sale right now. About $100 off of normal price. According to the 'camel' they do this mark down pretty regularly.
Limited-time deal: XTOOL D7S Automotive Diagnostic Scanner, Bidirectional Scan Tool, Upgrade of D7, ECU Coding, 36+ Resets, All Systems Diagnosis, Crankshaft Relearn, CAN FD & DoIP, 3 Years Updates

$367 XTOOL D7S Automotive Diagnostic Scanner, Bidirectional Scan Tool, Upgrade of D7, ECU Coding, 36+ Resets, All Systems Diagnosis, Crankshaft Relearn, CAN FD & DoIP, 3 Years Updates

https://www.amazon.com/dp/B0BTBQ1NR4

 

Just placed my order for the D7S for $366. I sure hope this thing is legit. I didn't exactly want to get into programming my truck but I got 100 miles to my last tank and the extended crank is killing me. I'm also getting paranoid about carbon buildup. Thank you and good luck all.

 

After commuting 10 or so days Mileage showing 15mpg. Up from 13.5mpg
Ethenol still at 0% (checked with torque pro and Xtool D7). Have filled up twice from 1/4 tank with E10.
Should it show above 0% yet?

 

Mine has been stuck on 0 for a couple months now, and I have used E10 gasoline. I’m in no rush for it to begin rising!

 

I'm on my 2nd tank of the cheap gas (85 or e10?).
My alcohol % is at zero from 80's and the LT fuel percentage is low, 4 % iirc. It's starting better and driving better too. I got a slight bump in MPG but hoping for more this next tank. Thanks for help all!!!

 

I got a FOXWELL NT510 Elite from Amazon for $159 that will do the reset and a bunch of other Toyota functions

FOXWELL NT510 Elite fit for Toyota Lexus OBD2 Scanner, Bi-Directional Diagnostic Scan Tool Full System Code Reader, All Service Oil EPB Brake TPS Reset Crankshaft Sensor Relearn, Auto VIN, Free Update

https://www.amazon.com/dp/B07Y2QMKJ6

 

Does it reset fuel trims simultaneous with fuel alcohol density reset, or do you have to reset each individually?

 

Not sure. I didn't see a function specifically for fuel trims. I reset the density and did the relearn procedure and everything is back where it should be

 

Glad y'all have found other scan tools that read and reset the alcohol fuel density. My Tundra's alcohol level remains at zero since I reset it one year ago and I haven't had any problems (still starts right up and gets much better gas mileage).

 

+1 for the Xtool D7. I reset my truck this past weekend and I'm seeing 15-15.5 MPG up from a max of 13.7. Definitely worth the money to anyone on the fence

 

So if I am supercharged what are signs of the alcohol level going up. Does it run richer along with the hard start?

 

I would imagine so. Might be worth picking up an Air/Fuel Ratio gauge if you have forced induction

 

I'm supercharged also and I haven't had any symptoms, but I do periodically check the ethanol percentage. Are you running HPTuners? If so, you can connect to VCM scanner and read the percentage and go from there. If mine creeps up then I'll probably buy one of the mentioned bidirectional scanners and reset as needed.

 

Mine does i wonder if this is normal?

 

MPG update: 15.7 average over about a 120 mile round trip this morning with about a 1,200 Ft elevation drop and gain on the way back. Not too bad for a N/A V8 spinning 35's at 6,000 Ft average elevation.

 

I was thinking for us FFV owners, it is. Maybe we can get a non-FFV guy to chime in and tell us if it says something else for them.

 

Winning!