Hondata

My Flex fuel sensor stopped working yesterday. Now it shows a constant ethanol content of 2.67% when I start the car but the fuel temp seems to work. When I turn of the igintion the fuel temp drops to 0. Where should I start to troubleshoot?
The tank is full of E85.

Edit
It seems like it show correct values for the fuel temperature but the ethanol percentage stays at 2.67%.

There may not be enough flow for it to read properly. There may be something clogging the fuel lines.

The flex fuel sensor is mounted between the fuel pressure regulator and catch tank with AN6 fuel lines. The engine is running fine. Can it still be a clogged return line?

It is that or a faulty sensor more than likely.

What software version are you using?

4.1.1
Could it be the beta software?

I re-tested with 4.1.1. and the ethanol sensor is working ok. I think it is your sensor.

Update
Tested the sensor with a Zeitronics display and the sensor worked as it should, testid with both e65 and e85 fuel.
What should I do now when the sensor is OK?

Check your wiring and re test in the vehicle.

It's working again. It turned out to be some sort of software bug. I uploaded a different cal file and then it worked.
There is some sort of software problem that can make the software show 3% when it is actually much more.
There also seems to be some sort of problem with using PLX wideband controller for closed loop as maybe every 10 or 15 time one starts the car the wideband closed loop doesn't work.

I suspect both issues are a noisy signal. I've had hundreds of runs without a problem, but you'll need to capture a datalog of the wideband closed loop not working in order to diagnose any further.

Regarding the wideband, when it's working it's working as it should and when it's not working it's not working at all and showing an afr of like 20. If it's not working I just turn off the ignition and then turn it on again and then it's working as it should again.

The Flex fuel problem was only solved with reloading the calibration file not like the wideband where you only turn of the ignition and then turn it on again.

I fitted my flex fuel sensor and was getting inconsistent readings plumbed into the return line shortly after the regulator. Would be 0% then jump to 90% for a couple of minutes then shift around again.

Contacted Hondata, then checked my wiring, changed my grounds, changed the power supply, Nothing was working.

Eventually just bit the bullet and bought a new sensor.... And now it's working like a dream!!

Can't believe I was supplied a brand new dud sensor:(

Hopefully these things aren't going to be as unreliable as they seem.

Mine as never showed any inconsistent reading except for when it only showed 3%.

It seems like it maybe worked only when the software was uploaded as it showed 73% which was probably correct at the time i reloaded the map. But it has since then showed 73% all the time although I have filled up with both e85 and gasoline. So it seems to be like before when it showed 3% all the time, but now it's showing 73% all time. I have tested the the sensor with a multimeter that can read Hz with different wiring and different power supply and it's been giving a perfectly stable signal no matter what ground or power supply that's used. So the wiring can be excluded as the problem. The temperature is also working as it should all the time. Another thing that makes me think it's something wrong with the Kpro 4 or software is that when I disconnect the sensor the Kmanager show 0 degrees in temperature but still 73% in ethanol content.