E85...any reason Not to use it?

[gooffeyguy]

Ok, now this is weird.....

Earlier after fueling up my ethanol % was fluctuating between 33 and 38 on the 2 mile trip home. Went to dinner about 15 miles away and it would jump from 9-something to 40-something then settled to 12.94. It stayed on 12.94 the entire way back. It ran strong, like it does on straight E85.

Now the 8-9 gallons of 93 that was in the tank before filling up had a 8-something ethanol %, then I added 10 gallons of 87 and 12 gallons of E85. You would think the current % would be more, unless the E85 that was put in had the lowest amount of ethanol allowed (51%)??

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[HiHoeSilver]

Ok, now this is weird.....

Earlier after fueling up my ethanol % was fluctuating between 33 and 38 on the 2 mile trip home. Went to dinner about 15 miles away and it would jump from 9-something to 40-something then settled to 12.94. It stayed on 12.94 the entire way back. It ran strong, like it does on straight E85.

Now the 8-9 gallons of 93 that was in the tank before filling up had a 8-something ethanol %, then I added 10 gallons of 87 and 12 gallons of E85. You would think the current % would be more, unless the E85 that was put in had the lowest amount of ethanol allowed (51%)??

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

Keep driving.

 

[derfman00]

Besides the tech2, is there another alcohol monitor?

 

[swathdiver]

Ok, now this is weird.....

Earlier after fueling up my ethanol % was fluctuating between 33 and 38 on the 2 mile trip home. Went to dinner about 15 miles away and it would jump from 9-something to 40-something then settled to 12.94. It stayed on 12.94 the entire way back. It ran strong, like it does on straight E85.

Now the 8-9 gallons of 93 that was in the tank before filling up had a 8-something ethanol %, then I added 10 gallons of 87 and 12 gallons of E85. You would think the current % would be more, unless the E85 that was put in had the lowest amount of ethanol allowed (51%)??

I had to drop the alcohol content on gas to 0% and E85 to 29% to get 13% with the amounts you pumped in. I suspect she's not done computing. Did the trims level out at zero while cruising steady or are they still jumping around? Mine takes about twenty miles to settle down usually but I've checked a few days later sometimes and it had changed again.

Besides the tech2, is there another alcohol monitor?

Yes! You can buy an OBDII Bluetooth adapter and download the Torque Pro app for your phone. Some guys even have the data project onto their aftermarket navigation screens instead of their phones.

 

[derfman00]

Yes! You can buy an OBDII Bluetooth adapter and download the Torque Pro app for your phone. Some guys even have the data project onto their aftermarket navigation screens instead of their phones.

Any recommend odbii? I normally would do this research, but my brain is fried from work (software developer) and I don't want to go down a rabbit hole. Thanks in advance for any help!

 

[swathdiver]

Any recommend odbii? I normally would do this research, but my brain is fried from work (software developer) and I don't want to go down a rabbit hole. Thanks in advance for any help!

I'm not the expert on this but I think the Torque Pro app people mentioned one on Amazon that works well. @kbuskill

 

[randeez]

i have a cheap like $15 bluetooth adapter for android, i think apple needs to use wifi.
just says "elm327 " on the side of it i think

torque pro app is $5 bux, but can be put on multiple devices after you buy it once.

 

[HiHoeSilver]

Ok, now this is weird.....

Earlier after fueling up my ethanol % was fluctuating between 33 and 38 on the 2 mile trip home. Went to dinner about 15 miles away and it would jump from 9-something to 40-something then settled to 12.94. It stayed on 12.94 the entire way back. It ran strong, like it does on straight E85.

Now the 8-9 gallons of 93 that was in the tank before filling up had a 8-something ethanol %, then I added 10 gallons of 87 and 12 gallons of E85. You would think the current % would be more, unless the E85 that was put in had the lowest amount of ethanol allowed (51%)??

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

Was it warm when you filled it up? How long did it did between refueling and driving to dinner?

 

[gooffeyguy]

Was it warm when you filled it up? How long did it did between refueling and driving to dinner?

I've used 8 gallons since filling up and it's still reading 12.94% ethanol content.

I think something was screwy with that E85. It was a Mobil station though.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[HiHoeSilver]

I've used 8 gallons since filling up and it's still reading 12.94% ethanol content.

I think something was screwy with that E85. It was a Mobil station though.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

Could be the gas, for sure. But with the VFFS, it will abort the calculations of you "do it wrong". I've had to reset mine before (never do this with e85 in the tank).

Fill it up warm. If it does the math while it's warming up, it gets gooofed up. Drive it for at least 7 miles following the fill up. This will give the best baseline result.

 

[gooffeyguy]

I had to drop the alcohol content on gas to 0% and E85 to 29% to get 13% with the amounts you pumped in. I suspect she's not done computing. Did the trims level out at zero while cruising steady or are they still jumping around? Mine takes about twenty miles to settle down usually but I've checked a few days later sometimes and it had changed again.

I've used almost a half a tank since getting gas and it's still showing 12.9% ethanol. My LTFT while cruising steadily on the highway will range from about 8 to 12. Around town it's lower, in the 2-5 range.


2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

 

[swathdiver]

I've used almost a half a tank since getting gas and it's still showing 12.9% ethanol. My LTFT while cruising steadily on the highway will range from about 8 to 12. Around town it's lower, in the 2-5 range.


2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

Mine runs the opposite usually. At highway speeds they zero out but stop and go they go up and at lower cruising speeds such as 40 mph they might be -3 or -5. Depends on the alcohol content too. It's an observation and not something I've tracked.

 

[HiHoeSilver]

I've used almost a half a tank since getting gas and it's still showing 12.9% ethanol. My LTFT while cruising steadily on the highway will range from about 8 to 12. Around town it's lower, in the 2-5 range.


2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18

Your trims are high because the calculated E% is lower than actual.

At this point, I would force a refueling event (put in more than 3 gallons) under the conditions I mentioned in my previous posts. Engine at full operating temp, followed by 7+ miles of driving.

I'm curious about more thing here that I haven't yet dug into. When you're mixing fuels, do you start the truck for just a few seconds and drive it over to a different pump? I'm assuming so and am not sure yet how that may /may not affect the VFFS calcs. Same question for you James. @swathdiver

 

[swathdiver]

Your trims are high because the calculated E% is lower than actual.

At this point, I would force a refueling event (put in more than 3 gallons) under the conditions I mentioned in my previous posts. Engine at full operating temp, followed by 7+ miles of driving.

I'm curious about more thing here that I haven't yet dug into. When you're mixing fuels, do you start the truck for just a few seconds and drive it over to a different pump? I'm assuming so and am not sure yet how that may /may not affect the VFFS calcs. Same question for you James. @swathdiver

I think's Tom is fine with his current mix, the trims are constantly adjusting and while driving it's tough to pay attention to them. Sometimes I'll do a data log with the Tech-2 or AutoCal and view it later on the computer, or get my daughter to drive while I play with the Tech-2.

As for your question, it has not mattered in my experience. I almost always refuel with the engine running too. A couple of weeks ago I refueled and then got the "We're hungry!" from the crew in the back seats, so we pulled right next door to Golden Corral. The relearn went off without a hitch afterwards and took the usual 18 miles to settle down on a number.

 

[gooffeyguy]

Your trims are high because the calculated E% is lower than actual.

At this point, I would force a refueling event (put in more than 3 gallons) under the conditions I mentioned in my previous posts. Engine at full operating temp, followed by 7+ miles of driving.

I'm curious about more thing here that I haven't yet dug into. When you're mixing fuels, do you start the truck for just a few seconds and drive it over to a different pump? I'm assuming so and am not sure yet how that may /may not affect the VFFS calcs. Same question for you James. @swathdiver

Same pump, different handle.

I stopped on my way home from work and the engine was up to temp. Shut off while fueling and not started until I was done. I only drove about 4-5 miles after that before arriving home.

I had 9 gallons of 93 octane in the tank before fueling with a 9% ethanol content showing on the gauge. I pumped 12 gallons of E85 then 10 gallons of 87 octane. I have no idea the % of E85 I pumped in, but from using this same station in the past it has ranged from 63% - 77% ethanol.

Ive got some running to do today, about 15-20 miles each way, and will top off the ~10 gallons and see what happens.

2001 Yukon SLT
2012 Yukon Denali XL
2011 Yukon Denali RIP 5/20/18