Hello! I bought my 97 Max last year at the beginning of the winter. I kept all the gas receipts and I'm getting 14-15 mpg all the time. Based on 50/50 city and highway. Since the high gas price these days, I deceided to tune my car a little bit. I changed my spark plugs to NGK Iridium IX and a new fuel filter. Air filter seems fine and I didn't change. Last night I filled up the car and I got 220 miles out of 15 gallons. So do I need a major tune up or will it get better with the weather getting warmer? Any suggestions are welcome. Thanks. =)

 

READ THIS. http://forums.maxima.org/showthread.php?t=512892

 

check for a knock sensor code. Redline SI-1 system cleaner. take out any heavy crap you dont need in your car.

 

whats ur driving habits ? heavy foot = gas burns faster

U bought the car last year before winter and air filter doesnt need to be replaced ? how many miles are on this filter ? if u were not the one to put it in when u bought the car then it might need to be still replaced

r u using 87 or 91 gasoline ?

 

i SERIOUSLY gained 100kms per tank by cleaning my KN pod filter.. was getting 420-450kms tops for a year odd (far back as I can recall lol) and now while still driving just as hard I get 550kms.. lightfooted I reckon I will hit 600kms a tank with 80%street\20% highway

 

Man, i've been running high test but I cant get over 285 miles to the TANK... it cost me 50 bucks to fill up last!!

i hit the highway for about 100 of those miles, and i was racing some, the rest was city going to and from work.

 

things to consider as far as maintenance (assuming no codes and good KS)

PCV valve
spark plugs
injector cleaning
TB cleaning

as far as everytying else goes, make the car lighter by not driving around with crap in the trunk (yes that inckludes ur subwoofer),

 

i think i'm doing my spark plugs and running some injector cleaner through it next. i've already cleaned the induction system and the TB. i just replaced my KS too.

 

did u clear the code ? u must do this

injector cleaner doesnt always work, i have yet to see any difference in my cars performance after 2 times of using different brands, i got 3 bottles for free recently so i will use them but i dont expect much change, but actually taking the injectors out to clean them is possible

i got SLICK 50 high mileage fuel system treatment, STP fuel injector cleaner, and WYNN's Signature series: Fuel system treatment

We'll c how that goes

 

http://forums.maxima.org/showthread.php?t=517993

 

I used to do a 250 mile highway trip every weekend. When I went by myself I would get 26-27 mpg, but when I took 3 friends with me I would get 28-29 mpg. It doesn't make much sense, but it's a big enough dataset that it's almost certainly not a fluke. One friend suggested that the added weight lowers the ride height and thus decreases drag... can anyone running dropped confirm or deny this? (Because if it's true, I'm dropping mine tomorrow )

 

Its been once said that if u take an F1 race car and THEORETICALLY speed it up to its maximum velocity upside down on a perfectly flat surface the air suction would keep the car from falling

Keep in mind F1 cars are like a few inches off the ground, i dont think a traditional drop would affect fuel economy so much that you would notice it

maybe u got more MPG because ur friends pitched in money for gas ?

 

i didn't notice anything after dropping mine. i noticed something when i put big heavy 18s on... lol i just switched to 17s and it seems a little better around town.

 

seafoam the TB, and fuel tank. check your MAF

 

Well something is definately wrong with alot of these pictures. I run 87, i havent changed a filter or oil in 2 years, and my rear brakes rub really really bad. I still get 300 miles to a tank. 20-21 mpg.

If you cant solve the problem and need to escape the high gas prices then i'll give you the best solution anyone can give you. This is a very easy way to get 60 mpg, and i have been doing it for about 2 months now. Ride a motorcycle. Its spring, the weather is great, and motorcycles can do 300+ miles on $10 worth of gas. Just my .02.

 

WTF???

 

Not sure how many miles on your 97 max. If more than 100k change your o2 sensors in the headers. Slow reacting o2 sensors can hurt your mileage if you drive a lot in the city.

 

Yeh im getting around to it, i simply dont drive my max very much anymore. At $3 a gallon i cant afford to. Motorcycles are more economical and to be honest, easier to repair. You only have three things that ever go wrong....carb, plugs, or fuses(given you ride a carbeurated bike like me).

 

What is the typical gas mileage that a 99 max gets anyways

 

Around 22 - 24 mpg city, sometimes less, 26-28+ highway.