Hey guys, I have a 2013 RS auto, and I recently added the advantage+ tune to the car. The first tank of gas I ran through was about the same as before the tune (~2mpg difference over all with idle to warm up on cold mornings). The second tank was about 1mpg less than that, but this current tank (which should have been better quality gas since it was from Shell instead of Wal-Mart) is terrible. Like ~10MPG drop from average. As far as I can tell, I'm not driving all that differently as my commute is the same, etc. Anyone else ran into this with the most recent tune? I love the power, but it's hard to justify a 30% decrease in MPG right now.
Massive MPG loss after Tune?
- Thread starter TN1.4T
- Start date
Blue Moon Sonic
New member
what octane gas and you went to walmart for a gas fill before going to shell?
Turning off cruise does not turn off the tune any longer. It is a dynamic program now that is supposed to be in ECO during normal driving and power when you need it.
Wal-Mart is much closer. I have to go out of my way to get to Shell (and it seems to be doing worse than big blue :-/)
Wal-Mart is much closer. I have to go out of my way to get to Shell (and it seems to be doing worse than big blue :-/)
Sneakerfix
New member
Winter grade gas could be the issue
Wouldn't that have changed in October? This is within a 2 week period?
You didn't mention octane ratings for the gas you used from each station.
Try a third party gas station with the same octane you got from Wally World.
MPG calculations are not binary, the best way to understand your MPG is multiple tanks over repeatable driving (which you seem to be doing) Also, I don't usually use Shell gas, just because of who is around me; I typically use, Sunoco, Mobil and BP; and have had consistent results over multiple tanks.
Burn through that tank, and try the Wally World gas again, or try a different station. One tank of poor MPGs isn't an indicator of a problem with the car so much as the fuel in the tank, IMO...
93 all the time. Even before the tune. I'll run a couple more tanks through it and see what happens. It may just be at the end of the day my car likes Wal-Mart Gas. It is an adopted Southerner after all...
I'm getting around 35-37mpg with the new tune around town, not highway, with 93 winter gas. I will admit, its a bit harder without eco mode now. I have to be MUCH lighter on the throttle. Having an UltraGauge helps. I have the torque output on display, and adjust my throttle to keep output under 60ft/lbs, when I can. Highest I've gotten was 43.8mpg, in eco mode, during the summer, before the new tune was released. All my numbers are calculated manually as the DIC doesn't always get it right.
mja
Site Supporter
I don't believe the mpg's should be that far off. I also don't think you'll need to wait for LTFT's to relearn trims too long and still be that far from what you used to be seeing. Something's off and may be causing it to go into an enrichment mode too early, whether it's from WOT PE, cat, etc. I'm assuming you're staying out of boost and not driving hard. Talk to your tuner (trifecta?? guessing). And it's not necessarily a BAD thing, just that the tuner has to send you a package deal that has worked closely on a similar setup, but needs some datalogs to set a few things right. Hope that helped w/out going into depth.
^^^ this.
If you want your tune more for MPG, but still have some benefit at WOT then tell whoever you bought it from. Maybe they can increase TPS/torque threshold so injectors don't spit gas into the motor as quickly. My guess is something's just off.
^^^ this.
If you want your tune more for MPG, but still have some benefit at WOT then tell whoever you bought it from. Maybe they can increase TPS/torque threshold so injectors don't spit gas into the motor as quickly. My guess is something's just off.
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