Gas mileage drop?

2012+ US/Canadian Civic Si / 2013+ ILX
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steve47co1
Posts: 22
Joined: Fri Feb 13, 2015 9:37 am

Gas mileage drop?

Post by steve47co1 » Wed Mar 04, 2015 2:02 pm

I have been getting very consistent gas mileage since 10/13 when my 12 Civic Si was last tuned on a dyno. On the highway, it was not hard to get 34mpg and 31 city (calculated).

Now, since I had to clean the water out of my gas tank, fuel lines, fuel filter, injectors, etc., my gas mileage has dropped (calculated) to 30 highway and 26 city.

Do the attached calibration and datalog* files from today tell you something that I am missing?

Thank you,

Steve

*One is a WOT run to 80 and the other is a mix of highway and city driving.
Attachments
3-4-15.fpdl
(679.82 KiB) Downloaded 71 times
wot 3-4-15.fpdl
(264.63 KiB) Downloaded 66 times
TC Retune-3-4-15.fpcal
(21.29 KiB) Downloaded 67 times

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Hondata
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Location: Torrance, CA
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Re: Gas mileage drop?

Post by Hondata » Thu Mar 05, 2015 8:39 am

The fuel trim is negative, especially at low injector openings. This will affect fuel economy.
fuel trim.png
fuel trim.png (37.4 KiB) Viewed 2566 times
Hondata

steve47co1
Posts: 22
Joined: Fri Feb 13, 2015 9:37 am

Re: Gas mileage drop?

Post by steve47co1 » Thu Mar 05, 2015 10:43 am

Thank you, Hondata! I will look into that.

steve47co1
Posts: 22
Joined: Fri Feb 13, 2015 9:37 am

Re: Gas mileage drop?

Post by steve47co1 » Thu Mar 05, 2015 6:43 pm

You were right. Very negative fuel trim; running super rich at WOT. My tuner sent me a revised map; I will data log tomorrow and see what it looks like.

Thank you.

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