Recently I got that 25K maintenance that I'm supposed to get with w cars and I noticed that I don't get the usual mileage that I get before the maintenance. Usually I get 40mpg but now I get at most 34mpg. I don't think it's my driving. Hell, I drive slower and try harder to get higher mpg than before so I was wondering if it's me... or is it the people who did the maintenance.

Any help would be appreciated.

Post pics of yourself so we can determine what the problem is.

What is done in the Civic Hybrid's 25k?

x2






try using 93 octane from shell, mobile, or chervon

when you use bad gas at a lower octane it tends to use more energy and burn faster.

thats as simple as i can put it

QUOTE

You or the maintenance guys may have accidentally disabled your Overdrive gear (I know I accidentally do sometimes). Every passenger car has an Overdrive gear, which is the gear that increases fuel economy. Almost all automatics have a button or switch that disables the Overdrive gear in order to increase driving power for things such as towing another vehicle. Look for a button/switch on your drive selector that says "Overdrive" or "O/D".

You may also have loaded your car with more weight since then. Extra weight increases your fuel consumption. Are you hauling more people or stuff in your car? An extra 100 pounds can reduce your fuel economy by as much as 2 miles per gallon.

There's a lot in driving habits and driving conditions that can affect your gas mileage. One thing that can really increase fuel consumption is high engine speed (engine RPM). While driving I try to cruise at around 2,000 rpm with my Toyota Corolla, and for normal accelerating I try to keep the rpm no higher than 3,000. Aggressive accelerating brings your engine speed to well above 4,000 rpm and increases fuel consumption dramatically as your engine injects a whole lot more fuel to get it running harder. Since passenger cars are optimized for the speed limits, speeding will typically have your engine speed higher than is optimal. So speeding also reduces fuel economy. Aggressive braking will also cause your automatic transmission to downshift at higher rpm's, keeping your engine in an overall higher rpm range. Another is excessive idling... that is, if you're in your car waiting for your friend to finish buying her Slurpee at 7-11, turn the engine off while waiting. It's not difficult to realize that idling gets zero miles to the gallon, but a lot of people still don't bother turning the engine off while waiting. This is also part of why stop and go traffic eats up more fuel. The other reason why stop and go traffic uses up more fuel is because it takes more fuel to accelerate up to speed than it does to maintain speed.



Negative on that. The octane rating isn't relative to the quality of the fuel. Yes a lower octane fuel burns faster, but in this case the Civic Hybrid is designed for 87 octane fuel and will not benefit at all from a higher octane fuel... if anything it can be detrimental.

The octane rating is just a number that determines the fuel's resistance to detonation, also known as engine knock. Detonation is bad for the engine. The car engineers design their engines for a specific octane rating based on what the engine is designed for. There are different variations to determining the octane rating, the US uses the Anti-Knock Index (AKI) method which is what I'll be using in this post.

A few factors that determine the octane rating requirement include (but not limited to):

1) Air/fuel ratio: the ratio of X parts of air per X part of fuel. The stoichiometric air/fuel ratio is 14.7:1. Higher than 14.7 parts air is considered lean, lower than that is considered rich. A higher octane rating allows a leaner mixture. Generally, for every two points increase in octane rating, a one point increase in leanness is allowed. Retune your engine to run a leaner mixture for a higher mile per gallon rating is not advised as it would take too long to recoup the initial investment costs (if that's even possible)... especially when you factor in the additional cost for higher octane fuel.

2) Compression ratio: the ratio of the volume that the air/fuel mixture is compressed. Most passenger vehicles are engineered for a compression ratio of 10:1. Many car enthusiasts working on lower-end cars (like the Honda Civic) tune their cars to run a higher compression ratio for more horsepower, which in turn will require a higher octane. Sports cars usually run higher compression ratios of at least 11.5:1 (such as the Nissan 370Z or the Ferrari Scuderia) and typically require 91 octane fuel.

3) Altitude: A general rule of thumb is that for every 1,000 feet above sea level, the octane requirement is reduced by 0.25 to 0.5. Forced-induction engines will typically be less affected by this since the intake pressure is more constant.

4) Temperature: For every 10-degrees Fahrenheit the temperature increases, an octane increase of about 0.5 is needed.

5) Humidity: As the humidity increases, octane requirement decreases. No figure available.

Consult your owner's manual in determining if you need to change your octane rating needs in regards to altitude and temperature. Though car designers will typically take into account a wide variety of altitudes and temperatures and optimize the engines to handle a wide variety of conditions with the same type of fuel via engine management computers. You generally won't need to worry unless you're in the extremes of temperatures or altitudes.

Using a higher octane fuel than your engine requires does not increase horsepower, burn cleaner, or lead to better fuel economy. In fact, running a higher octane rating than your engine is designed for can actually lead to lower power. With pump fuel, the loss in power is very minimal and you probably won't notice it. However for a standard passenger car using race fuel with octane ratings that exceed 110, it will be be noticeable. That's because race fuels actually have a lower energy content per volume and are designed to have lower density and resist detonation. The intent is to allow some pretty high compression ratios, which is how high performance engines achieve high power ratings using fuel with lower energy content.

Check this post daily, as technical posts such as this one tend to undergo numerous revisions for either technical corrections or clarifications.

check your tire pressure

i usually go 2-3 above recommended psi, bumpier, but doesn't bother me