Hi all,

I have a 2000 Maxima GXE. I bought it about a month and a half ago. I am seeking some help/advice on the following matters and would greatly appreciate any inputs:

1. The gas mileage on this car has been around 20-21 miles per gallon including significant highway driving. Nissan claims this car gives 21 city/27 highway but I have not had mileage of over 21 miles per gallon despite significant highway driving. Can anyone tell me why that may be? Do I need to do something to the car to get better gas mileage?

2. I use premium gas (91 Octane) for this car which is what I was told is required for this vehicle. Someone told me that the low gas mileage may be due to using Premium gas as it is more refined form of gas and burns faster than regular. So by putting regular, I may improve my gas mileage. I am not sure if its true or not but I would like to know the Pros and Cons of using regular gas versus premium for my nissan and also if using regular gas would improve gas mileage or not.

I would greatly appreciate any responses.

How fast do you drive? How hard to you accelerate? Premium gas (high octane) gas means just that. Less likely to detonate, engine ping. If you use lesser octane gas, you'll get less than desired performance and your engine will or may ping or knock. The thing about high octane gas burning faster is wrong. High octane gas burns less easily and that's why you need it for our engines, high compression. You should get better gas mileage with high octane gas. Check your tire pressure and all the usual stuff associated with improving gas mileage.

Could get into more complicated diagnosis... O2 sensors, emissions... air filter, fuel filter, if clogged? , so on. Drive with your windows open... many factors.

Thanks for the info. I normally drive at 75-80 mph on the highways and around 35-50 mph inside city. I use 91 Octane for fuel. I guess I will get a tune up done on the car soon and hopefully that will help a bit in improving gas mileage.

Thanks for your response.

keep all of your driving under the 3K RPM range and you will get numbers close to what nissan provides, even if you do, it might not even get 27mpg because city driving is a real gas killer

There's part of your answer. Like 95emeraldgxe said keep the RPMs below 3000 and you'll get better gas milage. Basically if you can hear your engine whine on the highway, then it's begining to put out more power and suck more gas. Also I've gotten 500miles from 16 gal of fuel once. That's around what, 31.25 miles/gal? Yea, that's great. But I drove around an average of 55-60 the whole time. Heavy steady traffic from my parent's house in CT to my place in Newport News, VA. So Nissan is right as to saying 500 miles to one fill up in a commercial. But you can't drive too fast....Basically the higher your rpms get. the more fuel you burn including reving.

I get 60 more miles per tank since I changed my fuel filter.....try that first

I consistently average 24.5 mpg in my 2000 GLE using premium gas. Of course over half my driving is on California freeways. And in keeping with my age, I don't drive as aggressively as I did years ago.

Just get a full tune-up if its near the time. My 99 gets great fuel mileage, i averaged 23mpg on my last monitored full-tank run, and that was with very very hard driving on my part. With a lighter foot i managed 25mpg, my foot cant get any lighter


eric

26.3 on last tank, 2k SE auto

26.3 on last tank, 2k SE auto

The Maxima gets terrible mileage in the city, unless you keep the revs below 2500 rpm and go the speed limit all the time. But who buys a powerful V6 engine to keep it under 2500 rpm? No one. With my 4th gen, which I maintain religiously, I get ~16-18 mpg in the city, and thats trying to keep it easy on the go pedal.

On the highway, I notice a huge difference if I keep my speed around 65, as opposed to 75-80. I get around 26mpg going 65, and around 22mpg going 75. I hear commercials on the radio saying how going 65 vs 75 saves 10% on fuel. I do not doubt that. It seems strange that would be the case, but try it out, you will notice a mileage increase immediately. Its hard to keep such a good engine turning a tad over 2000rpm on the highway when everyone is passing you, but thats what you need to do to get good mileage.

Now, if you have a 5-spd, then its different. With 5-spd it probably has more to do with shift points rather than the speed you end up driving at.

Thanks for all your responses; I really appreciate it. Well, even at 75-80mph on highways, the RPM is at 2500-2600 and rarely touches 3,000. In addition, I use cruise control on highways. As far as driving at 65mph, well the speed limit on our highways here is 70 mph and really I don't feel I can drive at 65mph in that case, lol. Still with 75-80 mph, the RPM is around 2500-2700 so the gas mileage should be around 25-27 on highways.

Anyway, I guess a good tune up and changing air filter may help as well as keeping the tire pressure correctly.

I appreciate all your help folks, thanks a bunch.

Do you have an auto? I have a 5 speed. At 3000 RPM, I'm going around 73 I think, so if you have a 5 speed, and at 75, you are definitely near if not at or past 3000 rpm. As for whether it's the shift points in a stick or what gear to drive on. It's still RPM, the fast the engine stays reving at a higher rpm, the more fuel it burns. That's why I'm always driving on 5th and wish I had a taller 6th gear on my 2000 max like the 2002+.

that sounds ironic. a clogged fiter would let less gas thru, as opposed to a new filter would let the gas flow freely with no clogging to restrict the passage.. i don't know.

Yeah - but lets not forget that wind resistance grows exponetially with speed. It's just one of those delimma's. On the one hand - an engine will be most efficient at that rpm where it produces its peak torque. On the other hand - you have wind resistance increasing drastically the faster you go. Taking gearing into account - I guess theoretically - there should be an optimum speed (rpm, gearing, whatever) which would give us the most economy. Maybe Stevtec can give us some input on this.

my 2000 se last time i fille dup i got 300 to the tank? sound about right? i drive 80% highway

holy resurrection...but to your question...i get at LEAST 350miles per tank, if not 370+...thats taking it to the E...just an FYI, i did get 30mpg two-three times, but i average right now about 24/25 mpg...mainly because of my bad coilpack