E85 issues

[mikeyss]

I've been running E85 consistently for about 8 months and I have much better throttle response and power than running on 93. I think mine feels slightly sluggish running on 93, that's why I made the switch to E85. I do a lot of city driving unfortunately, so my city mpg are about 11.5 mpg. It's about the same running either E85 or 93. Now on the highway, 93 does much better mpg wise.

 

[Mickey_7106]

i don't record it but i take a quick glance at every fill up. e85 is around mid 200's and pump is high 300s per tank. different stations for both types of fuels, always on RWD unless weather and road conditions are terrible

Mickey, have you been recording the mileage between tank fills? Were you using the same station? 4x4 or RWD?

 

[Mickey_7106]

if my cats were going out won't there be a code thrown?

 

[gooffeyguy]

Also remember, Not all E85 is created equal!

I usually run E85 from Mobil or Phillips 66, as they're the closest stations to me with it, and it runs good. I was out in St. Charles over the weekend and filled up with E85 at a MotoMart. Their E85 was $2.15/gal while the Mobil up the street was $2.42 (premium is currently $3.16). The MotoMart E85 doesn't feel as peppy/powerful as when I run the Mobil or Phillips 66.

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

 

[swathdiver]

if my cats were going out won't there be a code thrown?

Eventually. But mileage may decrease until the codes are thrown, happened to me. You can watch this happen with a scan tool like the Tech-2, not sure about the Torque Pro but @kbuskill knows.

However, the range you're describing is what I get usually:


11.4 MPG by 26 gallons is just shy of 300 miles for E85.


Ohh, let me ask you something since we basically have the same year and model truck, if you fill up right after the light comes on, how much does she usually take? Mine's about 25 gallons give or take 1.

 

[Mickey_7106]

The e85 in Berkeley is from propel fuels. No idea how that compares to others

I don't think I've ran in down till the light comes on. I vaguely remember pumping 29 gallons one time. Going on a trip this weekend, I'll try to get it low to see

 

[HACK BLOCK]

I truck runs smoother on e85 but I do feel less performance than 93

 

[machadosl]

Here in Brazil we don't have the E85 but a mixture of 73% of gasoline and 27% of ethanol, or I can use the mixture of 95% of ethanol with 5% of gasoline. Using any of then I do not see any difference on its performance only in fuel consumption, that is greater using ethanol. 7 mpg with ethanol and 11.7 using gasoline.
Another point is, if I only use ethanol, on the second time I fill the tank the check engine light comes on.

 

[esoteric_ast]

if my cats were going out won't there be a code thrown?

I ran a tank of 93 though mine and a cat started spitting codes like crazy. Next fill up was 87 and light never came back on.

 

[gooffeyguy]

To get more performance/hp when running E85, the programming/tune when running that fuel needs to have higher spark and fuel tables.

Usually the factory programming detects the alcohol content and changes it's programming accordingly.

Many tuning devices or tuners will change/optimize the fuel and spark tables to get the most power out of 87, 91, 93 octane fuel, but don't touch the factory E85 tables. I know DiabloSport doesn't change the factory E85 tuning, and I'm sure there are others.

So basically, if your vehicles factory tuning doesn't take advantage of E85's high octane and run higher spark tables when running it, then you won't feel any performance increase.

I believe GM states that the 5.3l when run on E85 produces 326hp vs the 315hp on 87 octane.

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