I own a 2005 FWD Ford Escape Hybrid.
I run E85 which is 85% ethanol ( grain alcohol ) in it.
I have a little box that adds 7% to the fuel injector on time.*
That is the only modification I made, and the car runs great.
Easy starts, smooth operation, no malfunction lights.
My tailpipe does smell like popcorn though.

I just ran on a 2,000+ mile round trip over 3 weeks through 7 states using nothing but E85... just to prove I could. I wonder how clean my fuel tank and delivery system is now?

Raw Stats:
2053 miles
147.69 gallons
13.9 MPG++
Lowest Price was $0.850 per gallon ( Yes, 85 cents per gallon! )#
Highest Price was $1.999 per gallon
Ave. Cost was $1.7445 per gallon

# I was in the right place at the right time to find the promotional pricing, but was only 6.4 gallons down, so only got 6.4 gallons at that price.

Cost per 2053 miles while towing: $257.65
To beat that on gas while towing, I'd need to get better 19.55 MPG.
That was probably not possible with the head winds I encountered.
But is so close to equal in cost, one cannot say with certanty one is better than the other.

++ Towing a 3200 lb. box trailer ~ 60 MPH.

NOTE: I specifically wanted to use E85 when towing since there seems to be a power advantage, while a MPG disadvantage. What I mean is, to pull that trailer 60 MPH on gas, the engine runs at 4500 RPM. On E85, my engine was pulling 60 MPH at 3500 RPM. I don't know about later models, but in the 2005 there is a huge noise difference between 3500 and 4500 RPM. So putting whether it is more powerful or not aside... you can't even listen to the radio at 4500 RPM, and at 3500 RPM you hardly notice the engine.

Second, the engine water temp ran 10 degrees cooler on E85.
Third, the generator motor ran 40 degrees cooler with E85. ( due to the lower sustained RPM's ? ).

Ethanol, good stuff, if you can get it at the right price.
Oh... I carried 5 gallons of extra E85 in my trailer. Two times the E85 stations were too far apart to make it on 1 tank. Without the trailer, I could have made it through CO, WY, SD, ND, MN, IA, NE with nothing but E85. It is that prevalent out here.

* The FEH has 28% extra fuel injector ability built in. E85 requires about 30% extra fuel to be added. My little box adds 7% ( adjustable ) so my FEH never "maxes out" which is generally what turns on a check engine light. One time, and one time only, in Nebraska, at -15'F and running on ethanol I got a check engine light. Due to the cold, the FEH was trying to add greater than 35% from "gas" ratio. The next day was warmer, and the light went off and never came back on.

 

addendum to post #1

The FEH does not have a coolent water temperature sensor.
It is inferred from the cylinder head temperature.
Thus, really, I should say, the CHT temperature was about 10 degrees cooler when running E85 at highway speeds.

 

I try to read up on studies, but sadly, read so much, I loose track of where I find stuff. BUT what I post here can be found elsewhere.

A governmental agency is testing the feasibilty of E15, E20, E30 in older, traditional vehicles. 16 vehicles from 1999 to 2007 are currently being tested.
Vehicles were chosen for study, based on number of sales in the U.S. to get a good cross sample of the U.S. Fleet.
None were "flex fuel".

An interim report came out on the on-going evaluation.
Cars were "used" and had between 10,000 and 100,000 miles on the odometer before the testing began.
16 out of 16 ran with the same, or cooler catalyst temperatures under normal conditions. 9 out of 16 ran with cooler catalyst temperatures under all conditions, including sustained Wide Open Throttle ( WOT ). 7 out of 16 ran with an average 30'C hotter catalyst temperature at WOT. It was inferred ( buy them, not me ) that the 9 that stayed cool used the modified fuel trim maps at WOT, and the 7 that got hotter did not use fuel trim maps at WOT and therefore, ran lean and created hotter exhaust temperatures.

No failures or harmful effects were observed in ~1000 miles of tests per car.
None of the 16 cars had any check engine lamps or other MIL lamps come on.
All 16 had lower CO emissions.
All 16 had lower NOx emissions.
All had greater ethanol emissions ( unburned fuel ).*
All had greater, but still trace amounts of formaldehyde emissions.*

* Went up in a linear fashion with % ethanol blend on the order of 0.03% to 0.08% IIRC.

 

I did a two week run (almost 2400 miles) using blends between E20-E30. The photo was taken on my return trip from Wisconsin around 35 miles from where I live.

 

Neither does a FE.

 

Going back some years ago a FT of more than 30% would turn ON your CEL. I had a vacuum leak and watched the FT hit 30% numerous times then turn the CEL ON.

Are you monitoring FT or injector pulse width? Injector PW isn't a commonly known PID.

Wondering how you intercept FT corrections and add 7% for one thing?? The O2 sensor(s) would catch any changes and make corrections anyway! How can you fool a O2 sensor??

 

It's quite simple. My FEH never passes +28% fuel trim, so it never sets a CEL.
The box prevents it from exceeding the normal range of values.
The box adds it's "adjustment" after the FEH's own adjustment.

Thus running on pure gas, the FEH fuel trim will go to -7% to cancel out the box. The car is happy, and all runs well.

Yes, the O2 sensor is really running the show, even on E85.
Fooling the O2 sensor, which I don't do, can help boost E85 MPG by 5-10%.

 

Isn't that a continuse process of the O2 making corrections and your box altering that?

 

The box is dumb. It add's a fixed amount of injector "ontime". It does not change on the fly.

Basic Schematic:

FEH Computer --> Fuel Injector Wire --> Box --> New Fuel Injector Wire --> Stock Fuel Injector x4

It takes the FEH output and adds x% to it and sends a new output.
That's it.

Knowing what I know now, it is so simple, that I would not have paid for it if I could do it all over. Except it comes with OEM plug n play connectors, that saves one from having to cut & splice, and returns the car to "stock" in about 60 seconds.

 

Okay, got it now.