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Discussion Starter · #1 ·
(Disclaimer: I already know all about 30%+ larger injectors, larger fuel pump and all that, this is strictly about the Flex Fuel Sensor.)

So the more I read about e85 the more I am sold on it. Not to mention it is all over the place locally and very cheap ($1.50gal) so that is a huge plus.

My only problem is I can't any info on the flex fuel sensor install due to Cobb and their crap over priced kit. Not only do they not offer one for pre-08 models, bit their "big" release have saturated the search results.

So does anyone have any information on the FlexFuel Sensor setup and install? The wiring?

Thanks,

-Jay
 

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I think their sensor merely detects ethanol percentage to display on the accessport, right? I mean you CAN run E85 without one.

Some thing to point out is that YES, you will get to buy cheaper gas, and it's plant based, which is super cool, but at the same time, you'll be dropping down to (roughly) 12mpg, so fuel savings are actually negligible for most people. Another reason lots of people don't do it is fuel gelling. It can have very hard starts in cold weather, so if it gets cold near you, it could be an issue.

It's a win in most other aspects, especially if it's readily available near you!

Im sure you already know most of that, but others may not, so just thought I'd throw it in.
 

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Discussion Starter · #5 ·
Yes, it drops that much.

It flows 30% more than pump gas, thus a 30% drop in mpg. more efficient burning but less efficient in consumption in that respect, if that makes sense.

I was speaking to a member here and when he was explaining the FlexFuel Sensor to me, he told me that it would detect the octane and switch the tune accordingly. This is the one from actual Flex fuel cars like a Fusion or Malibu. I think it was Robin ( MainFrame).

At least that is how I understood it. Maybe I understood it wrong? Someone Correct me if I am mistaken.
 

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Yes, it drops that much.

It flows 30% more than pump gas, thus a 30% drop in mpg. more efficient burning but less efficient in consumption in that respect, if that makes sense.

I was speaking to a member here and when he was explaining the FlexFuel Sensor to me, he told me that it would detect the octane and switch the tune accordingly. This is the one from actual Flex fuel cars like a Fusion or Malibu. I think it was Robin ( MainFrame).

At least that is how I understood it. Maybe I understood it wrong? Someone Correct me if I am mistaken.

Ahh, I see what you're getting at now. Makes sense. You want to be able to run whichever one you want, whenever, without switching the tunes. It seems like a sensor from some other vehicle would HAVE to be cross compatible.
 

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I've been running an ECA since 2009, but simply having the FlexFuel sensor (I'm using an OEM one from a GM vehicle) and gauge (Zeitronix) doesn't make the car FlexFuel capable. It just gives you a read out of ethanol content in your fuel. To make the car actually run FlexFuel you will need the proper ECU calibration (modified rom and a good FlexFuel tune). Cobb's implementation of FlexFuel with the AP is the best option for the OEM ECU so far. You can also do it with ECUTek, or open source using the Carberry Rom.. or, since Cobb has no plans to release FlexFuel capabilities for 02-05 models, you can also run standalone engine management (which is the route I'm going).
 

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E85 has 30% less energy density compared to pump gas, but it can be run leaner. The realistic decrease in MPG is arou d 20-25%.

Sent from my SAMSUNG-SM-G890A using Tapatalk
 

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Discussion Starter · #9 ·
Sorry guys, been really busy this week. Just now seeing this.

Ahh, I see what you're getting at now. Makes sense. You want to be able to run whichever one you want, whenever, without switching the tunes. It seems like a sensor from some other vehicle would HAVE to be cross compatible.
Yep, that's what I am looking and they compatible. The tricky part is what I want, which has been explained..

I've been running an ECA since 2009, but simply having the FlexFuel sensor (I'm using an OEM one from a GM vehicle) and gauge (Zeitronix) doesn't make the car FlexFuel capable. It just gives you a read out of ethanol content in your fuel. To make the car actually run FlexFuel you will need the proper ECU calibration (modified rom and a good FlexFuel tune). Cobb's implementation of FlexFuel with the AP is the best option for the OEM ECU so far. You can also do it with ECUTek, or open source using the Carberry Rom.. or, since Cobb has no plans to release FlexFuel capabilities for 02-05 models, you can also run standalone engine management (which is the route I'm going).
Ah, Robin. Just the man I wanted to see. Thanks for clarifying! Yeah, just like the thread title, "screw Cobb." Three reasons why I got the AP; convience with it's mobility and simplicity, free tuning software and a promise of FlexFuel capability.

Guess how many of those are left?

Anyway what EMS are you going to run?

http://finelineimports.net/index.php?main_page=product_info&cPath=1_6_194&products_id=127

I found this interesting blog post where Fuel Line Imports use a Link G4 SA ECU that auto detects octane levels and adjusts the tune accordingly. Which is exactly what I want, and am sure everyone else wants.

Here is a link to the Link (see what I did there?)
http://finelineimports.net/index.php?main_page=product_info&cPath=1_6_194&products_id=127

Let me know what you think of link (I am killing myself over here.)

E85 has 30% less energy density compared to pump gas, but it can be run leaner. The realistic decrease in MPG is arou(n)d 20-25%.
True.

And it is at least 57% cheaper to fill up with e85 locally. $1.64 v $2.85 for 93 octane last I checked. So yeah, definitely still worth it for the switch.
 

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Discussion Starter · #10 ·
And before anyone says "you'll have to run it "x" amount of time to see the "y" profit after the price of the conversion!"

I just did the math, I'll save $1,635.92 in a year running e85 even with a higher fuel consumption. So it'll pay itself off in over/under a year depending and I'll see more money in my bank account for car parts.
 
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