my gas mileage sucks

[todd_tampabay]

Originally Posted by vetkiller

Wow, I cannot believe some of you are getting below 25mpg. I drive 70/30 mostly highway and never get below 31mpg. I usually shift around 3.5-4.2k with the occasional romp above 5k.

I'm thinking it could be one of several factors, primarily:

(1) oil brand (car loves mobile 1)

(2) fuel brand (i always use marathon as I get extra 25 miles per tank)

(3) exhaust type (my high flow cat & exhaust gives me at least 1-2 extra mpg)

(4) season ( i always get 3-4mpg higher in the summer months)

(5) shift timing (shifting smoother means less engine hesitation and more momentum)

(6) highway driving (keep it 60mph and under as every mph after that uses exponentially more fuel)

(7) don't live in the 6-8k rpm range

I always get in the 340s+ for a full tank in the summer months.

you should be getting better ecnomy during winter months, due to the colder air its more dense therefore your car breathes better and you get a more efficient combustion, plus 5-10 more hp depending on temperature. Thats why they inventer the "Cold air Intake"

[Phillycivicsi]

yo do you get better gas mileage with a aftermarket intake im might get a short ram i guessin u do because better air flow i also put breathers on my car i unplugged the hose going from the engine to the intake and put breathers i gives me better mileage than b4 and i feel a lil smoother on the downshifts
im gonna take pics now so yall can see what im talkin bout

[Murderjetz]

...you think driving in cold weather gives you more horsepower?

sure keeping the engine cool is beneficial, but there's a point where it get's TOO cold. as in, your whole car is frozen and stiff from the cold. which requires more power to make everything run properly.

[Murderjetz]

Originally Posted by Phillycivicsi

yo do you get better gas mileage with a aftermarket intake im might get a short ram i guessin u do because better air flow i also put breathers on my car i unplugged the hose going from the engine to the intake and put breathers i gives me better mileage than b4 and i feel a lil smoother on the downshifts

They say that you do but I hadn't noticed a difference when I put one on my Mustang. Therefore I probably won't bother putting one on the Civic. And the HP gain is negligible, not really worth it IMO, unless you do other performance mods along with it.

what are these "breathers" you mentioned?

[vetkiller]

Originally Posted by todd_tampabay

you should be getting better ecnomy during winter months, due to the colder air its more dense therefore your car breathes better and you get a more efficient combustion, plus 5-10 more hp depending on temperature. Thats why they inventer the "Cold air Intake"

It's not from driving, it's from warming my car up.

[vetkiller]

Originally Posted by Murderjetz

what the hell, dudes...

I get 39mpg. Although I do drive mostly highway, and I usually shift at 3000RPM. I turn the engine off if I think I'm going to be idling somewhere for more than 10 seconds, like when I have to stop for a train at a train crossing.

Starting your car takes the fuel equivalent of 1 minute of idling so unless you will be there for more than a minute, just let her run.

[todd_tampabay]

little filters about the size of your fingers, ive seen them but i dont know if that does anything to be honest. as far as the mpg, i got a hybrid cold air/ram air intake and an exhaust and i get 30 mpgs easy its an lx but that doesnt matter, i still red line it gettin on the high way or to cut someone off and still get 30 mpgs, so im sure that my engine is gettin bettter mpg's because its able to breathe better, and yes when its colder outside it feels faster and i drive longer on the same tank.

as far as too cold, probably i dont know i live in florida so i cant argue that point either way...

[Phalanx]

I average about 28mpg and I sit in an hour of stop&go traffic in the morning and afternoon (2hrs total)... and I hit Vtec multiple times a day

[todd_tampabay]

Originally Posted by vetkiller

Starting your car takes the fuel equivalent of 1 minute of idling so unless you will be there for more than a minute, just let her run.

yea i agree i think thats a BAD idea

[Phillycivicsi]

this is my breathers on my intake

[vetkiller]

Originally Posted by todd_tampabay

little filters about the size of your fingers, ive seen them but i dont know if that does anything to be honest. as far as the mpg, i got a hybrid cold air/ram air intake and an exhaust and i get 30 mpgs easy its an lx but that doesnt matter, i still red line it gettin on the high way or to cut someone off and still get 30 mpgs, so im sure that my engine is gettin bettter mpg's because its able to breathe better, and yes when its colder outside it feels faster and i drive longer on the same tank.

as far as too cold, probably i dont know i live in florida so i cant argue that point either way...

I live in MN so yeah, a world of difference. When she has been sitting outside for a while I have to let her warm up for at least 2-3 minutes.

[volvo9]

Originally Posted by vetkiller

Starting your car takes the fuel equivalent of 1 minute of idling so unless you will be there for more than a minute, just let her run.

Not nowadays with fuel injection, but was true with carb's which just pissed fuel inot the engine. That's why Hybrids shut down their engines all the time.

[Murderjetz]

Originally Posted by vetkiller

Starting your car takes the fuel equivalent of 1 minute of idling so unless you will be there for more than a minute, just let her run.

I heard that with today's modern cars, starting your car takes as much as gas as idling for 10 seconds. And also that you're better off to just start driving after 30 seconds if it's really cold rather than let it sit for a while. It warms it up faster and wastes less gas. I don't know, it's what I heard on TV or something somewhere.

I still like to let it warm up for a good ten minutes when it's been sitting outside in a cold winter day, just so everything doesn't feel quite so stiff.

[RageOn]

19 around town! u have to be jumping on the juice more then 40% of the time. I make it a point play around off the red lights because that's what I bought the car for and I'm getting 25mpg around town. When I hit the highway i'm getting between 29-31 depending on extra bodies in the car.
I have a 1998 F250 so anything better then 15 city and 16 highway is golden. I feel like i get butt raped every time I take the truck out on the town.

[I Vtec, do you?]

Originally Posted by Murderjetz

what the hell, dudes...

I get 39mpg. Although I do drive mostly highway, and I usually shift at 3000RPM. I turn the engine off if I think I'm going to be idling somewhere for more than 10 seconds, like when I have to stop for a train at a train crossing.

I once read starting the engine is the equivalent to idling for a minute in terms of gas usage.

Nvm looks like vetkiller beat me to it.

[civicracer32]

The short trips can kill your mileage. The car, or all cars run rich until they do what's called "closed circuit looping." Basically reading real time engine parameters and adjusting the mixture/timing accordingly. Prior to the engine warming up(typically 160F water temp), the engine runs off preset parameters/estimations which cause the car to run rich and get not as good fuel economy. 5 minutes each way to school may be just enogh to get the car warmed up. This could be, and most likely is your answer to your poor fuel economy.

[gregk]

maybe you're burning that crap with ethanol in it.