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if you are getting less than 27mpg
Posted: Tue Sep 18, 2012 1:53 am
by 11zukizashi
unhook your battery for several hours. i was tinkering around inside my doors and i unhooked it for a good portion of the day (took a steak break in the middle) and after i was done my 24.5 average mpg started at 29.5 then it dropped to a steady 27.7 and i am doing the exact same driving as before 90% city stop and go. seems like one of those "unplug it and plug it back in" fixes for just about every other piece of modern electronics. cheers.
If I am getting less than 27mpg......
Posted: Tue Sep 18, 2012 3:21 am
by WESHOOT2
.......I am traveling a significant portion of my miles in excess of 100 MPH.
Re: if you are getting less than 27mpg
Posted: Tue Sep 18, 2012 2:58 pm
by NiteRider
11zukizashi wrote:unhook your battery for several hours. i was tinkering around inside my doors and i unhooked it for a good portion of the day (took a steak break in the middle) and after i was done my 24.5 average mpg started at 29.5 then it dropped to a steady 27.7 and i am doing the exact same driving as before 90% city stop and go. seems like one of those "unplug it and plug it back in" fixes for just about every other piece of modern electronics. cheers.
That doesn't even make any sense. Not saying you're wrong but I would be completely dumbfounded if this were the case.
Re: if you are getting less than 27mpg
Posted: Tue Sep 18, 2012 4:10 pm
by KuroNekko
It may be because of an ECU memory reset. Not sure on the details, but I've heard that many modern cars have ECUs that learn your driving style and adjust to that. Disconnecting the battery not only clears your radio presets, but clears the ECU as well. Maybe this is why, but are you getting this figure from the car's display or actually doing the math?
I don't trust the electronic read-out and cars always seem to overestimate mpgs on their displays. I will start comparing avg mpg on the screen to miles traveled divided by consumed gas in gallons.
Re: if you are getting less than 27mpg
Posted: Wed Sep 19, 2012 12:54 am
by murcod

It could be the car giving inaccurate readings, or the service station pumps not metering the fuel accurately and giving you less than you paid for. Or a bit of both.
I'm quite happy with my average so far - 8.9l/100km . I live in a hilly area and don't have many long straight stretches of road without lights on my daily route. The average is equal to my previous much smaller vehicle after it had the ECU programmmed and a free flowing exhaust fitted.
Re: if you are getting less than 27mpg
Posted: Wed Sep 19, 2012 2:48 am
by Firefly
Your mpg meter was reset, as mine is programmed to at fuelings. It will be high for a while if the drive from the station is smooth, or work its way up slowly from 9 to 10 to 12 and so on if its going up hilly roads for a bit, but it will eventually settle in to around the same. If you never had your mpg guage reset, or if not for a while, you may be seeing a difference - and probably better mileage if the engine is now more broken in, or if the weather is more agreeable.
Re: if you are getting less than 27mpg
Posted: Wed Sep 19, 2012 12:03 pm
by ipaqxman
24 mpg average with 90% city stop n go? Thats... Amazing... My POS 19 mpg...
Re: if you are getting less than 27mpg
Posted: Wed Sep 19, 2012 4:08 pm
by 11zukizashi
obviously the mpg gauge is reset, i reset it frequently when i was geting 24 as well. It has settled in to 26.5 since i had the battery unhooked. definately worth the 4 or 5 ratchet turns to disconnect the battery and reconnect it after a few hours. i have done 170 miles and im still a solid tick away from half a tank.
Re: if you are getting less than 27mpg
Posted: Thu Sep 20, 2012 3:31 am
by murcod
I should have added my average is over 1500km from new and I've never reset the trip computer (It was actually reading 16.0l/100km when I test drove my Kizashi!) It's been dropping the whole 1500km and I think will drop below 8.9 in the next week or two. Mine's also the 6spd manual.
I love the amount of torque the engine has, no need to rev it hard to keep ahead of the normal traffic flow. I've only used sixth a couple of times as I'm normally driving in 50 - 60km/h zones with the occasional 80km/h.
I'm impressed given the engine isn't really all that high tech compared to new generation engines with direct injection etc. I'm getting better economy than when I was driving my Mum's new 2012 Kia Rio 1.6l direct injection 6spd auto driving the same routes.
Re: if you are getting less than 27mpg
Posted: Fri Sep 21, 2012 3:05 am
by ~tc~
To hell with what the computer says - when you divide miles run by fuel put in, has it changed?