Hello, I need some help on Fuel Economy. I have a 1997 SE, Auto. I did a search for fuel economy and found people getting from the low 20's to low 30's, depending on driving conditions, etc.

I live in Houston which is flat and warm. I average 16 mpg combined city/highway. My Sentra has an EPA sticker of 22/28 MPG and gets 25 on the same daily route. From this, I conclude that something must be wrong with this maxima(I just bought it).

I have checked and adjusted my tire pressure. I have checked my air filter, it's fine. The alignment is dead straight. I have not yet checked the spark plugs, but the engine runs smooth as silk, and has plenty of power. There is no check engine light on. The brakes are not grabbing. The transmission is not slipping (at least as far as I can tell). I currently have about 42k miles on the odo.

Other than spark plugs, is there anything else I can check?

 

By any chance are you driving with the overdrive off? Leave it on all the time down there in TX. Unless your playing....

 

By any chance are you driving with the overdrive off? Leave it on all the time down there in TX. Unless your playing....

 

Are you making a lot short trips, like 5 miles or less?

I find that during my weekday commute, which is like 3 miles in the city, I get horrible mileage, like 15MPG. On the open road, with no stopping, I get around 26MPG. If I drive like 90% freeway and 10% city, overall mileage plummets to 20MPG....my Max gets HORRIBLE city mileage.

 

I get 165-180 miles on 14 gallons on only city driving, where I make short trips like 3-5 miles each.

I did everything on My maxima such as: spark plugs, oil filter, tune up and fuel filter, air filter and none of it helped to save my gas milleage! I drive in NYC.

 

Well, I just filled up again. 21 MPG after a highway trip of about 200 miles, then another 100 miles 'regular' driving. It seems 28 might be reasonable if the tank were all highway, but 21 is out of the question for city driving.

My commute is 12 miles each way, 9 of which is freeway. There is no stop and go traffic. Short runs for lunch, sometimes dinner at night. Other than that, it is parked in the garage.

It seems as though I'm going to have to live with this poor mileage.

 

The true destiny of the 4 speed automatic transmission in the Maxima is for poor fuel economy -- The torque converter is the main culprit --

For stop and go driving:
the torque converter NEVER locks up in 1st or 2nd gear -- there is about a 15% average efficiency loss just accelerating the car.

The torque converter ALMOST NEVER locks up in 3rd unless the RPMs are up to around 3200 RPMS (about 65MPH)--

The torque converter never locks up in overdrive at RPMs lower than 3200 (about 90MPH) unless there is very light throttle/torque application -- forget about keeping the converter locked if accelerating up a more than mildly steep grade or acclerating sufficiently to pass another car on the freeway --

Keeping the car in gear while at a stop (holding foot on the brake) consumes about another 10% more fuel as compared to putting car in neutral --

Heat lowers viscosity of the tranny fluid -- which reduces the mechanical efficiency of the viscous coupling of the torque converter even further -- so even worse efficiency and acceleration in hotter weather --

I have driven other cars in which the torque converter locks in all gears at a wider range of RPM and throttle opening -- which translates to better acceleration and efficiency --

Relatively tall gearing makes engine work harder/longer to accelerate to a given speed or to maintain a given speed.

For an apples to apples comparison, a 5 speed manual would probably get 3-5 more miles per gallon as compared to an automatic for the same conditions --

 

Get a 5-speed

 

A 5-speed was my first choice, but I couldn't find any for sale at the time I was buying. I'm 33 years old, and this is my first automatic transmission (I've had 15+ cars). I'm not impressed.

 

The thing is that the 5 spds are soo rair you really have to be lucky to come across a good one...It took me about 3 months to find mine but I was really lucky and persistant...I love 5spd and I will never switch when it comes to a sporty car.

 

On my first tank of gas on my second Maxima I got 17.7874 miles per gallon (just got gas today). But since this was the first tank, I wasn't that light on the throttle. Oh, and since it is my first 5spd Maxima I had to play a little.

98 SE 5spd

On my old 96 SE auto, I got around 19-23 in the city I think. And yes, I had some what of a heavy foot then too.

So, I think you should be getting better than you are??? You are using premium gas right???

 

You don't need a 5-speed Max to get better gas mileage. By the time my '95 hits 30mph it's in overdrive and gets mid-20's mpg city and 29 mpg highway. Either something's not right with your engine or you just have a serious lead foot.

 

you just have light foot...5spd is better if you want good gas milage...I'm not saying auto is bad at all

 

This is almost always true, but for the '95-'99 Max it's a slightly different story according to the EPA ratings:

4 speed auto 21 city/28 highway
5-speed manual 22 city/ 27 highway

 

Wow OD at 30mph!! That's some serious light footing. I usually don't get a shift into OD until at least 40mph. On normal acceleration for me, the 1-2 and 2-3 shifts occur at 3000-3500 RPM. Any lower and it almost feels like the engine is shortshifting.

 

Maybe because i'm starting to mellow out at age 34 . i also have a '72 Olds 442 with 300hp/400tq at the rear wheels, but lately i've been wasting it's potential with my "old man" driving habits.