I fill my tank to full and I run out usually within a week (if that!)

Today started with a half tank an drove about 50 -60 miles and was down to a quater of tank!
Same thing happened Saturday, started off at 3/4 and about a 20 minute drive later I was down to 1/2 a tank.

I know this is not right... its killing my pocket...
What can I do to fix? What can be causing this problem?

Is there anyway you can check the knock sensor to see what shape its in and know if it needs replacement or not?

 

Learn how to check for codes by looking in the faq's.
Also, the key to figuring out gas mileage problems is to know your actual gas mileage. Fill the tank, reset tripometer, drive to almost empty, fill tank again, divide number of miles by the number of gallons put in the tank.
Again, read the faq's, there's a guide to good gas mileage incl. air filter, fuel filter, spark plugs, knock sensor, tire pressure, etc.

 

how often should the fuel filter be replaced

 

Try to fill up your car when you're at the 1/4 tank mark. Don't go all the way to empty.

 

Replace the fuel filter every 30,000 miles.

 

http://forums.maxima.org/showpost.ph...6&postcount=39

 

I would bet that you have a bad O2. They usually affect the gas mileage. Is the CEL on?

 

whats the cel and can the 02 be checked to see if its bad or not?

 

i have the same problem, really kills the wallet, especially since im a full time student

 

I was getting 13-14 mpg and i changed my KS [which was giving me a code] The ks was cracked in 1/2 when i took it off. Replace it with 1 i bought off a org member for $20 and 90,000 miles on it but i now get 19 mpg. I t made a huge difference in power as well.

 

CEL=Check engine light.
Check the stickies on how to run the codes and also what each of the codes means.

I get appx 30mpg on my max even at 205K! I wouldn't tolerate anything less. I recently changed my KS and it has pickup just like it were new off the lot! I venture to guess that's it's one of the two or both causing your problems. How many miles are you on?

 

You really need to fill your tank and then when you run down to half or 1/4 then fill it back up and find out your TRUE mpg. Just basing your gas mileage on $10 fill ups isn't going to give you a true estimate on mpg.

 

I get about 300 mpg... It varies from about 285 - 310. Is that normal?
I am on 83,000 miles. Should I get a knock sensor?

I was offered a knock sensor from a maxima.org member with 60,000 miles on it for 20 bucks.

 

Do you mean 300 miles per tank? 300 miles/gallon would be extremely awesome.

How do you drive your car?...do you have any mods? Are you 5spd? Highway driving or street mostly?

 

You haven't stated what kind of driving you do. I can get 500 plus miles on straight highway driving and 350 plus in city commuting. Why waste your money on a used knock sensor? And by the way mpg or miles per gallon is not miles per tank.

Fill the car up. Drive it to below 1/4 tank or until the idiot light comes up. Fill it back up to the brim or where you figure it was before. Determine how far you drove (using the trip odometer between fillups) and divide by the number of gallons used = mpg. Elementary, my dear Watson, lol!

 

300 miles per tank.
I drive my car usually slow to start then once i hit about 50 I press the peddle, usually going normal about 80, but go pulled over this weekend so now Im driving the speed limit (thanks to the Lord the cop did not give me a ticket)

Its a 6 CYL, 95 Nissan Maxima SE. I mostly do Highway driving to the city or 30 minutes to work, very rarely is it stop and go

 

Case in point...

I drove to Kansas City a week ago. On the way up there I stayed between 60-70mph and got about 450 miles to the tank. (Manual usually gets a little less mpg highway than an auto)
Driving back to Dallas I was a bit more spirited...going WOT a lot of times and averaging about 80mph on a whole tank. I got about 350 miles to the tank.

Driving habits play a major role.

When was the last time you had a tuneup? I am hesitant to just say replace your KS because most people with KS problems average around 200 miles to a tank.

 

I just got the car about 4,000 miles ago.
SinceI have had the car I have done 2 oil changes and 2 oil filter changes. New muffler. Transmission fluid flush. New brake fluid.

What type of tuneup do you mean?

 

spark plugs, fuel filter, then bigger stuff if necessary

 

Always do the cheaper maintenance type stuff if you know you might need it.

Tuneup would have been one of the 1st things on my mind after buying a used car...you just never truly know how well maintained your car was from the previous owner.

 

How often should my brake fluid be changed? and any tune ups I need every so many miles that you could tell me would help.

Thanks

 

well i live in nyc and i get 200 for the whole tank....allthe way from thr F to the E

 

With my max I averaged 29.8mpg on a 900 mile trip from Ohio to South Carolina (yes through mountains!) crusing between 80-90mph, with an average right around 87mph. On that trip I crossed 500 miles on one tank of gas. Normally, with a mixture of city/highway I get about 400 miles per tank and about 25-27mpg.

Change your fuel filter and spark plugs. Check ECU codes for KS or o2 sensor.

 

You can calculate your MPG with $10 fillups, but you'll have to start and end with a full tank. What I usually do:
- Fill the gas tank all the way and reset the mile counter
- Fill up with $10-$15 worth of gas when I get near the 1/4th mark and I save my receipts for every fillup (so I know how many gallons I put in)
- About once every 2 months I fill it up the tank all the way to full
- Then: (total miles driven/number of gallons)=MPG

Last 1500 mile average was about 17.5 MPG (winter fuel and rush hour traffic) and coming up on another 1500 mile average soon