bujeezus

so i've noticed on multiple occasions that when i baby the gas, my mileage is actually worse than when i romp on it. i'm talkin like a 45 mile difference per tank. what gives? could this be a symptom of something? i mean i got no problem with "spirited" driving. i just don't want to overlook an issue. thanks all.

Modell

maybe dirty/bad pcv valve. maybe higher rpms breathe it better as opposed to lower...but I am just guessing. Ive been reading about these things affecting mpg.

bujeezus

i was kinda worried about it being a faulty vtec. from what i understand it's the "fuel efficient" version not really the "performance" version. i'm just guessing also.

98civdx

What car do you have?
Have you done any sort of maitence? How many miles are the car?

What is a faulty vtec???

Libertariat

joelmatt89

you should give a little more details, what do you mean by romp on it, put this in terms of rpms. Also what method are you using to calculate mpg and how many tanks of gas have you observed this problem over.

bujeezus

'00 coupe ex, manual transmission. 198,000 miles. changed the timing belt and water pump around 170,000. run full synthetic, change the filter ever 5k miles an the oil every 10k. when i say "romp" i mean push the gas pedal to the floor. not popping the clutch at 5k. i divide the number of miles i get between fill ups by the number of gallons i put in the tank. what other method is there? i noticed this every other tank for 6 tanks now.

Former User

Gas mileage is the sum of all the types of driving you do between a fill up. Maybe when you romp on it you balance it with high mpg freeway driving and when don't romp on it you doing mostly low mpg city driving.

vartok

also, do you always stop at the same gas station on ruffly the same day? If not, could be fluctuating gas quality... Some of the stations around here, if you get gas when the tanks are running low, it picks up alot of trash (i dont go to thouse at all, so i dont worry about it) also i have noticed that some cars like some brands of gas better. But it really depends on your local supply

98civdx

Have you done a tune up at all? cap,rotor,plugs etc.

A lot of people will say I am only imagining a difference, but I swear I get better MPG when I get gas at shell compared to when I filled up at arco.

bujeezus

i don't think that's it. i commute 90 round trip every day and no driving on the weekend. i'll baby from the front door to work and back and get less miles per gallon than when i get on it from door to door.

bujeezus

i thot of that so i started using this shell station off the interstate exclusively for my little experiment.

bujeezus

haven't changed the cap and rotor just the plugs and wires. maybe there's somethin goin on there?

98civdx

I don't think it would hurt to do it.

What octane are you runing? 87

BryCivicSi

Where do you live? Temperature fluctuations can play a big part is fuel consumption. Colder air is packed with more oxygen. So on colder days, your car will use more gas compared to warmer ones.
I've noticed I am getting better gas mileage. I did a tune up over the summer and with normal driving my mileage went up to about 29 MPG with spirited driving. Over the winter even if I babied it, I was lucky to get 24. It is now getting warmer and warmer here in Chicago and I am getting close to 26+. Once we switch over to summer fuels again, hopefully I can start getting close to 30 again. Not bad for a B16A2 and I rarely put highway miles on it.

bujeezus

that may be it. live in alabama and you know what they say, "if you don't like the weather here, wait a day. it'll be totally different!" ha!