What did you do to your NNBS GMT900 Tahoe/Yukon Today?

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iamdub

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ya I have added cleaner on full or empty tank, they probably just say "full tank" on the product that so people won't complain if it made the engine run goofy for some god forsaken reason

People usually are using additives BECAUSE the engine is running goofy. But, you know people are gonna ***** no matter what.
 
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I only have a 92 oct tune from BB so not sure how it would react to some e85
From what I understand, the E85 tables (spark/fuel) are seperate from the regular fuel tables. Many tuners don't mess with the E85 tables.

I run the 93 (or 92/91 whatever it is) octane Diablo tune and run E85 when not running 93

The thing I'm not sure is at what Ethanol percentage the ECM switches tune tables. @swathdiver
 

iamdub

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I only have a 92 oct tune from BB so not sure how it would react to some e85

If yours is FlexFuel, it'll still adjust for it. How accurately is the question. The virtual sensor seems to be so hit-or-miss. At 65% alcohol content, the most mine would read was 22%-23%. In addition to the MPG hit, it's a waste when running it for power and cost savings if it doesn't fully adjust for it. The fuel will still have its cleaning properties, though.

Actually, I think my testing took place way back before I did the engine work, which included new upstream O2 sensors. Now that my tank is really low, I might try half a tank of E85 and repeat my testing. But now I'm trying to determine when I actually tested it cuz if I remember it at all, it couldn't have been that long ago.
 

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If yours is FlexFuel, it'll still adjust for it. How accurately is the question. The virtual sensor seems to be so hit-or-miss. At 65% alcohol content, the most mine would read was 22%-23%. In addition to the MPG hit, it's a waste when running it for power and cost savings if it doesn't fully adjust for it. The fuel will still have its cleaning properties, though.

Actually, I think my testing took place way back before I did the engine work, which included new upstream O2 sensors. Now that my tank is really low, I might try half a tank of E85 and repeat my testing. But now I'm trying to determine when I actually tested it cuz if I remember it at all, it couldn't have been that long ago.
yes it's a 2012, my mpg is about 11 on 92 no matter how far or short I drive, drove all the way up as far north as you can go this summer nice long drive 11mpg lol
 
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