Mixed 2 Gal of 101 with 91 Issue / Question

[Robot3RK]

Mixed about 2.1 Gal so technically still 92 instead of 93 I believe. Wanted to test if there was any small difference. I forgot to check the K.Con so I will have to check it out later but I have a question. Right after fueling in 101 on top of the 91, the Mile Range stayed the same. Is this normal? Is the ECU still adjusting for the new higher added octane fuel mix? How often do you need to mix? Got 101 Octane from 76 Gas which had VPRacing fuel I believe for the 101. I am on Phearable Stage 1.5 Non-SI Tune mainly on just Map 1.

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[U.S.C]

I mix 1.5 gallons of e85 with the rest 91 and my count is always much better.

 

[Robot3RK]

I mix 1.5 gallons of e85 with the rest 91 and my count is always much better.

When you first did the mix. Did it affected your driving range? I haven't done the e85 route, just tried the 101 and 91 mix route first but noticed the range number didn't change for some reason.

 

[dellyjoughnut]

I would not expect an increase in mileage unless the fuel had less or no ethanol unless you cheat the results by resetting the trip meter before/after fueling and driving on the freeway for 30 mins.
Two gallons of 101 isn't going to have a significant effect. Try 70% to 90% filling tank with 101.

Good results can only be calculated after gaining sufficient data like filling your tank with just pure 101 for 8 fills. It just leaves too much to an error and "got better numbers".

 

[Robot3RK]

I would not expect an increase in mileage unless the fuel had less or no ethanol unless you cheat the results by resetting the trip meter before/after fueling and driving on the freeway for 30 mins.
Two gallons of 101 isn't going to have a significant effect. Try 70% to 90% filling tank with 101.

Good results can only be calculated after gaining sufficient data like filling your tank with just pure 101 for 8 fills. It just leaves too much to an error and "got better numbers".

Not talking about MPG but the Fuel Range available left in the tank. The number did not update right after adding 2 gallons which maxes out the tank fill. The red gas needle meter increased back to full I think but the Fuel Range number on the dash tactometer stayed the same. I guess either the fuel mix was no good and messed something up in the car or it's because I refueled with this mix on top early since the tank still had a good amount filled. I usually get gas when the needle drops below half. I guess since this is the first time I changed my fueling pattern the computer couldn't update the range properly? I'll probably just stick to pure 91 no mix from now on and resume back to normal refills. Hopefully that will fix this issue.

 

[U.S.C]

When you first did the mix. Did it affected your driving range? I haven't done the e85 route, just tried the 101 and 91 mix route first but noticed the range number didn't change for some reason.

Nope nothing changed with that at all on mine.

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