2012 Fit, CVT, 100k KM, getting poor gas mileage (i.e. 9.7 l/100km) after doing the following:
-Air Filter
-Changed all 8 plugs [put in Denso IKH20TT]
-Replaced O2 sensor [put in Denso 234-9117]
-Cleaned MAF
-Ran injector cleaner
-Cleaned ERG (besides carb cleaner, used dremel brush on openings and on springy shaft)
(I though maybe I knackered my EGR but I don't have the typical idle/running symptoms for that)
-I did a battery disconnect reset for an hour.
-CAR RUNS GREAT--very smooth, no rough idle, accelerates fine, I drive with a feather foot.
So why has my mileage gone from about 6.7 or 7.2 l/100km to 9.7?
Here are my OBD readings. But I don't really know how to read them. Any advice greatly appreciated.
I believe these were all taken at idle (except for the one that shows 0 RPM when the Auto Stop probably kicked in). My A/F stays very close to 14.7.
THANKS!!

 

There's way too many variables to firmly determine. Just drive it. Unplugging and forcing the car to relearn will impact mileage until it trims fuel tables back to what works. You also should consider winter fuel blends versus summer blends. We've switched in the states, I don't know when the switch is overseas.

I absolutely don't trust generic OBD data. It's largely wrong or inaccurate. Especially if you're using the app Torque. It'll read some data correctly but completely flubs the lion's share. OEM data is what you want if you're trying to get a live snapshot, and those devices are much more expensive.
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Hi Red 05. Thank you for your response! It's interesting that you disfavor Torque; I'd always heard pretty good things about it and that's why I put the app on my phone..
Herut

 

I tried it way back when, but more likely than not it would read implausible data for something (22 volt battery voltage, sub 1.0 AFR, inconsistent oil/water temp readouts) and I tried two different OBD Bluetooth readers to rule out the reader being at fault. I could trust it to clear engine codes on friend's cars but I would not trust it to read sensor data.