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Discussion Starter #1
I just put my first tank of gas in my '13 i Touring hatch after purchasing it ~2 weeks ago. Surprisingly my avg MPG only came out to 29.2 MPG with conservative hwy driving and some city driving. I did some poking around and it seems people recommend resetting the ECU. I couldn't find a specific explanation on how to do this. It seems like the ECU is reset by disconnecting the battery for "x" amount of time, but then what? Am I jumping to conclusions that resetting the ECU could help more accurately recalibrate the system to equate to better fuel efficiency?
 

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You reset the ECU by disconnecting the negative terminal of your battery and fully discharge any residual charge stored (capacitance) by waiting a few hours or pumping the gas pedal/turning on the lights if you are impatient.

If you haven't done any mods like exhaust or intake since you got your car you don't need to reset your ecu. The idea behind resetting the ecu after these mods is to have the car relearn the current conditions so you don't run too lean/rich and negatively impact your mpg.

Your lower than expected mpg is likely a function of it being brand new car and the first tank of gas ever is not enough of a sample size to judge what mpg you are averaging.
 

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Discussion Starter #4
Ok, thanks for the clarification. I guess I'll hold off on the ECU reset since the car is bone stock. I'll give it some more time and see what happens. I guess I was just a little surprised since i was getting about 23mpg in the '12 Golf R I got rid of.
 
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