9th Gen Civic Forum banner

1 - 14 of 14 Posts

·
Registered
Joined
·
10 Posts
Discussion Starter #1
When I bought my 2012 civic EX at 45000km(28000 miles) last summer I was able to go as low as 6.2l/100km(37.9 mpg). Then the cold winter came and the consumption went as high as 8.5l/100km(27.6 mpg) during the whole winter. And I guess this is normal in winter time. Now the warm weather is back to 27-30 deg Celsius(80-86 Fahrenheit) and I cannot go as low as last summer. I'm stuck at 7.0l/100km(33.9 mpg). I know it is not a big difference but I would like to know what can be the cause ? Same driving habits. Econ was on last summer as it is right now.

Throw whatever you can think of.

- Spark plugs ?
- Tyres ? they are at about 5-6 32th.
- Air filter ?

The car is now 62000 km(38000 miles). Oil has been changed as per iMid.

TIA
 

·
Registered
Joined
·
333 Posts
Try sea foam or fuel injector cleaner? Is tire pressure the same now as before? Buying gas from a different location with maybe a higher ethanol content? There's alot of variables to the equation, these are where I would start. I don't suspect anything wrong, but if your goal is fuel consumption, then that's awesome. If you find something that makes a big difference, let us know.
 

·
Truck? What truck?!
Joined
·
27,158 Posts
When did you take the mpg ratings?

I ask because in most places there is a 'winter' gas that turns in considerably worse mpgs than summer gas. If you took the reading right at the changeover point, you could have either missed the changeover, or the car hadn't had time to adjust. These cars have ECUs that need a little time to 'learn' what's changed.
 

·
Truck? What truck?!
Joined
·
27,158 Posts
My '12 EX sedan gets 21 to 23 MPG, 99% short trip driving...
I would be happy with anything in the 30's.

Have you replaced the tires?
These cars seem to be all over the place, mpg-wise.

My '12 LX with a 5AT consistently got 23 to 25 mpg on my daily work commute, and the best I ever got was 42.5 on an all highway ride of about 2 hours.

My '15 LX with the 5MT gets about 28 mpg on the same commute, but the best highway mpg I have been able to achieve has been 38 mpg.

Although both 5-speeds, the AT pulled lower rpm in 5th gear at a given road speed, probably accounting for the greater mpg. But the city driving? I can't account for that consistent ~4 mpg difference in the MT's favor, unless my driving habits in the 5AT and 5MT are that different in slow stop-and-go traffic.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #6
@9thgensifamily : You have a good point here. Yes I switched gas station last fall because of credit rebates and incentives. So it might be the cause. Once this tank emptied I will try another gas station.

@scottyrocks : I commute about 40 miles a day. I use a whole tanks at every other week. So I'm pretty sure I have summer fuel in the tank. Thanks for your input. It could have been a factor.

@Teeps : Same tires. They were removed last fall for winter. Most of my commute is a state road. So no stop and go traffic for me. Most of the time at around steady 50 mph.

Forgot to mention I have a 5MT on mine.

So my next step will be to use gas from another station and see. I will also make sure the tire pressure are according to spec.

I will report back with the result.

Thanks for your time !
 

·
Registered
Joined
·
1,507 Posts
as other's have mentioned, there are so many variables that account for mileage. one of the biggest variable in mileage besides fuel are tires. what type, the rolling resistance, size, weight of tire are just some of the factors. ambient air temps, including pressure can have an effect on mileage. weight in the car, A/C on or no. traffic, both cabin and engine filters. type of oil used (full synthetic vs. conventional and weight of oil used).

set your tires at factory specs. run a few tanks. log your results for mileage. then, bump up the air pressure 3-5 lbs, then run a few tanks, log the results.

i just went back to using non ethanol, 93 octane fuel (pure gas). cost more. mileage went up from around 38-40 for my morning/afternoon commutes to 44-47 mpg. probably not financially beneficial to me, but the throttle response is much improved, especially when the A/C is on and it's over 90 degrees here. with the regular 87, i can't get out of my own way sometimes (hot outside and A/C on).
 

·
Registered
Joined
·
891 Posts
Damn.. I'll keep my old AF 2012 Si...

CIVIC 2.jpg
CIVIC 1.jpg
CIVIC 3.jpg

Marko!
 

·
Registered
Joined
·
13 Posts
My 2012 EX averages around 32-33 MPG. I use gas from Costco, commute about 80 miles each day, with occasional local trips. I'm at about 120K miles. Econ button doesn't seem to make a difference.
 

·
Truck? What truck?!
Joined
·
27,158 Posts
Yeah, I don't use econ either. All it does it slow acceleration. No improvement in mpgs.
 

·
Banned
Joined
·
58 Posts
I use Econ and it improves my mileage approx. 2-3mpg. consistently and I prefer it for drivability. Unless you, the driver, override what Econ does, it has to work.

I consistently get 33 to 34 in city driving and just returned from a thousand mile mixed interstate and two lane trip and the iMid showed exactly 40.0mpg. I just used Top Tier any brand gas of both regular and premium octanes depending on price at the time. Mileage usually boils down to driving habits, terrain, and traffic IMO. Do check what other's have advised though. FWIW.
 

·
Truck? What truck?!
Joined
·
27,158 Posts
I use Econ and it improves my mileage approx. 2-3mpg. consistently and I prefer it for drivability. Unless you, the driver, override what Econ does, it has to work.

I consistently get 33 to 34 in city driving and just returned from a thousand mile mixed interstate and two lane trip and the iMid showed exactly 40.0mpg. I just used Top Tier any brand gas of both regular and premium octanes depending on price at the time. Mileage usually boils down to driving habits, terrain, and traffic IMO. Do check what other's have advised though. FWIW.
I like the econ on my wife's '18 Accord because it lessens the turbo-lag of the 1.5L engine. With econ off, you hit the pedal, nothing happens, and then whoosh! With econ on, it's all smoother, if slower. Either way, no new turbo for me.
 

·
Registered
Joined
·
10 Posts
Discussion Starter #13
Ok here is my results... after a couple of gas tank from another station the mpg improved just a little , I cannot get the consumption below 6.8 l/100 (34 mpg). I swear I was able to easily reach 6.1 l/100 last summer.
My guess is that my summer tires are at about 5/32 th. So next summer I will replace them and see.

Thanks all for your input on this !
 

·
Registered
Joined
·
1,403 Posts
I like the econ on my wife's '18 Accord because it lessens the turbo-lag of the 1.5L engine. With econ off, you hit the pedal, nothing happens, and then whoosh! With econ on, it's all smoother, if slower. Either way, no new turbo for me.
Unless you get a new bigger turbo.....
 
1 - 14 of 14 Posts
Top