PRL Flex Fuel + Bluetooth OBDII Reader Scanner = How to Read Ethanol %?

youCTR

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YES, I KNOW I CAN READ ETHANOL % WITH HONDATA FLASHPRO + HONDATA MOBILE APP! I'm just looking for a simpler solution with a cheap bluetooth OBDII reader and a generic mobile app. I mean...most importantly, I don't want to be carrying around my FlashPro in my car that's: a) long and cumbersome, b) expensive, and c) exposed to the summer heat.

Anyway, I've already purchased a bluetooth OBDII reader and tried a mobile app (DashCommand trial), but it didn't work out. The ethanol % reading was at "no data". I had a feeling that it wouldn't work since the PRL unit doesn't seem to send the ethanol data through traditional OEM flex fuel methods. So I guess one way I'm asking about this is how is Hondata calculating the ethanol %? From there, how can I program a mobile app (e.g. DashCommand, Torque, etc.) with a custom PID so that I can get a proper ethanol % reading?

IN BEFORE: "you should've gotten the SiriMoto Flex Fuel kit that comes with an ethanol gauge then".
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YES, I KNOW I CAN READ ETHANOL % WITH HONDATA FLASHPRO + HONDATA MOBILE APP! I'm just looking for a simpler solution with a cheap bluetooth OBDII reader and a generic mobile app. I mean...most importantly, I don't want to be carrying around my FlashPro in my car that's: a) long and cumbersome, b) expensive, and c) exposed to the summer heat.

Anyway, I've already purchased a bluetooth OBDII reader and tried a mobile app (DashCommand trial), but it didn't work out. The ethanol % reading was at "no data". I had a feeling that it wouldn't work since the PRL unit doesn't seem to send the ethanol data through traditional OEM flex fuel methods. So I guess one way I'm asking about this is how is Hondata calculating the ethanol %? From there, how can I program a mobile app (e.g. DashCommand, Torque, etc.) with a custom PID so that I can get a proper ethanol % reading?

IN BEFORE: "you should've gotten the SiriMoto Flex Fuel kit that comes with an ethanol gauge then".
Look for ect2(engine coolant temp 2), that is what hondata uses for the ethanol signal. Also why are you worried about keeping the flashpro in your car. I leave mine in the car 24/7 and it gets hot as hell in the summer here in Kansas.
 
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youCTR

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Also why are you worried about keeping the flashpro in your car. I leave mine in the car 24/7 and it gets hot as hell in the summer here in Kansas.
Like I said...a) long and cumbersome: the FlashPro is just an awkward piece of hardware to me. It gets in the way when it's plugged in, and it's just...everywhere. I want a unit that's small and compact, can easily plug in and out, and not be in the way.
b) expensive: $700 FlashPro vs $20 OBDII dongle...I think this is a no-brainer here. I'd rather be messing and throwing around a $20 piece of hardware than something that's $700 and locked to my ECU. I'm not too worried about the heat (I was piggy-backing off the expensive part) but I'd rather have the $20 unit be the workhorse and take the beating.
 

ssjoeboe9

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I don't even know how you could create a custom PID to give ethanol reading.. but I guess if you know the method then go for it. Usually those apps don't give you enough control to do something like that. Really it's pretty straight forward. Hondata takes voltage readings from ECT 2. 0.4V-->4.8 where 0.4V=0% ethanol and 4.8V=100% ethanol. You only need to assign this ratio to ECT voltage ratio. I'd almost say you're better off making your own little programmable raspberry pi & gauge, then again at that point why not just buy a universal programmable ethanol gauge and run off of ECT2 voltage.
 

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boosted180sx

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i just routed the wires to the flashpro along the bottom and into the bottom compartment area and it doesn't get in the way of anything. Can't even really see it when i'm driving.

The eca will convert the Hz signal to a voltage which then gets read by the ECT2 sensor which then looks at the table you set and then puts out a percentage.
you'd have to buy an ethanol % gauge which you can set the 0-5v reading as what % and get the reading off of the ECT2.

It wouldn't be possible to get that information through OBD2. at least i don't think it would be possible.
 

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It wouldn't be possible to get that information through OBD2. at least i don't think it would be possible.
I'm thinking the same thing. Stealth mount the FlashPro or external gauge in this case.
 

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Well i dont want my WRX i would rather have the C8.. it’s a cruel world.

They also said he could get an external gauge. It cant work from the obd2 (unless he finds a way to read ect2 voltage).
 
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youCTR

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You still need a tune to run more than E15-E20.
OP doesn't want a Flashpro
I am tuned with my Hondata FlashPro. I'm just trying to find another way to read ethanol % through the OBDII port without my FlashPro.

It wouldn't be possible to get that information through OBD2. at least i don't think it would be possible.
I'm thinking the same thing. Stealth mount the FlashPro or external gauge in this case.
It cant work from the obd2 (unless he finds a way to read ect2 voltage).
If it's not possible to read ethanol % through OBDII, then how is it possible I can read ethanol % through Hondata when my FlashPro is connected to the OBDII port?
 


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youCTR

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I don't even know how you could create a custom PID to give ethanol reading.. but I guess if you know the method then go for it. Usually those apps don't give you enough control to do something like that. Really it's pretty straight forward. Hondata takes voltage readings from ECT 2. 0.4V-->4.8 where 0.4V=0% ethanol and 4.8V=100% ethanol. You only need to assign this ratio to ECT voltage ratio. I'd almost say you're better off making your own little programmable raspberry pi & gauge, then again at that point why not just buy a universal programmable ethanol gauge and run off of ECT2 voltage.
That's really helpful, thank you. I'll take a look around and see if I can get this to work. If not, I can always return my OBDII dongle.
 

boosted180sx

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Yes I did. I'll take yours and the other post, and see if I can figure something out. Thanks.
The ethanol sensor reads a hz signal and then the eca converts that into voltage.

The voltage then is sent to the ecu through the ect2 plug and then it looks at the voltage to ethanol % table you set and displays that as a percentage.

There are lots of things the flashpro reads that obd2 doesn't. Things like fuel pump duty, knock retards, etc

he used an innovate kit that includes the gauge similar to what the sirimoto kit is.
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