i have an auto 98 max. i drive 90% city and 10% highway. my driving style is somewhat aggresive. i usually redline the max once or twice everyday. i get around 320 miles on a full tank and this equates to 14mpg. there are no codes, spark plugs have been replaced. car has 79,xxx miles. does anyone know what is causing the bad gas mileage?

 

328 mi on a full tank = 17mpg (you have an 18.5 gallon tank)

That sounds ok if youre driving hard...

 

How are you calculating MPG? You should fill up a full tank and reset the trip odometer, then drive till empty and refill (preferably at the same pump) full and see how many gallon your car takes and divide that by the amount of miles on the trip odometer. Example: 350 miles driven divided by 10 gallons of gas= 35mpg.

If this is what you are doing to calculate, then I would do a tune up. Replace spark plugs, fuel filter, air filter, oil change (if needed). Do you have any Check engine lights? If so I would check the codes also.

I would also re-think your driving habits if you are concerned with gas mileage.

-Nick

 

Does that mean you run it completely dry?

2nd grade math > you

Should be common knowledge around these parts.

 

also, PLEASE READ THE FAQ'S

there is a post in there that will advise you on what to check if your mileage is bad. however i'd quit driving my auto 'aggressive' if my mileage was poor. read the faq post and properly tune up your car and lay off the throttle and you should see improvements.

 

Fill up your tank and take a nice trip on the highway. Drive at least 100 miles, then top off your tank. If you mileage increases to between 26-30 then your fine.

 

eh u might have the same problem I do, your flooring it all the time

feel the powa!

 

Check the air pressure in your tires too.

 

It might be the winter mix fuel most gas stations are using now. The winter mix has additives that help to prevent your fuel system from freezing, but it also kills your mileage.

My MPG went from about 24 down to 20 over the past few tanks. Since I drive 300 miles/week for work, mostly highway miles, this is killing my wallet.

 

i've had the same decrease in MPG. i have a 100 mile round trip commute to grad school twice a week after work. boy am i glad the semester is over.

 

:attention:

I wonder if you were in undergrad, your mileage would be better?

 

probably! i've got a full library of books in my trunk these days... the emptry beer cans from a couple years ago weighed less!

 

FTW ...

 

You may not have a check engine light on but that does'nt necessarily mean that you don't have codes. I have a 96 with 164k and my gas milage decreased dramatically from around 380 in-town miles to 280-290/tank. I read alot of the posts concerning possible problems and decided to check ecu anyway. When I checked ECU turned out that there was a code which turned out to be knock sensor. I'm not much of the mechanic but from what I read in the posts and in the manual is that when the knock sensor goes it basically puts your engine in safe mode. Since it does not work properly you may even notice slight hesitation or hiccup at idle. I even noticed that through 1st and 2nd (I have and auto...unfortunately) that on hard acceleration that car would sometime pull hard to redline and others it would seem like I was already in 3rd or 4th. Anyway, took advice from the posts, purchased new KS on ebay for $73 and purchased the tools to install myself (you'll save a ton if you do it and you can with a little patience) I'm now back to the 18-20mpg around town. If you have'nt ever checked the codes it's easy. You may even find you have multiple codes. Read the FAQ's and it'll give you a step by step. Good luck.

 

what are some of the averages for a full tank? I'm getting like 350 ish but i have a code for rear 02, waiting for my y pipe cause stock one is junk

 

Rear O2 soesn't affect MPG, 350 sounds about right ... Stop thread hijacking because it's

 

my car can get 350+ but i dont really wanna take it down to that low. i do average 22 mpg. But i'm a very easy going driver. Mainly city. driving.

 

I found that I get good gas mileage if I drive the car like my grandma does, basically keeping things at 3kPRM and under. However, when the need for speed gets to me and I start driving stick like its meant to be driven, gas mileage pretty much takes a dump on its own back. LOL

 

why do you redline that thing? calm down with your driving dude, don't redline that thing, do all the engine things wit the plugs and all like everyone else said, i got a 99 max 5speed, i squeezed out 245miles on $20 before, i get around 400-420 miles on a full tank of gas and i live in jersey, im lucky its cheap out here, i plus is 2.07 a gallon and super is 2.15 a gallon, if anyone has the nerve to even bother asking what the price is on regular, please, buy another car, if you use regular on your maxima then you dont deserve a maxima, but other than that, dont drive aggressive and you'll get better mileage, i think thats fairly obvious, and on i agree with what you said, you drive aggressive and you redline a couple times a day, so there you go, the days i race around smokin these civics and accords and acuras around town, i most definately lose a good maybe 30-80 miles worth of gas just by accelerating hard all day, i could burn a full tank in 2 days doing that, but wheres the sense in that? its your driving style that ultimately what defines the answer to your problem