ok i'll start with i get 115 miles on 10gal what can i do i dont know what to do

 

fuel filter,plugs,O2?? for starts...what kinda gas 87/91??

 

Do a tune up and get new front oxygen sensors (call up oxygensensors.com and mention maxima.org for 10% discount - pay with a CC)

 

knock sensor
end of story
read the stickies

 

yea seriously ... read the stickies ... this guy is wack ... SPEAK ENGLISH !!

 

KS alone won't kill the gas mileage by that much

 

Do you have a CEL? When was the last time you: checked the tire pressure, changed the oil and filter, replaced the fuel filter, air filter, PCV valve, spark plugs, used fuel injector cleaner, eg. Chevron Techron, etc. etc.

 

Maybe your rear brakes are binding too... are you sure you don't have a fuel leak?

 

no cel
new oil almost brand new air filter pcv valve done spark plugs i got only 10k miles on them (njk)

 

ye and i have brand new ks

 

What about the other suggestions? You failed to anwser them ...

 

Yeah...Stickies would help. Do a tune-up, and check your tire pressure.

 

everything was done still having same problem

 

Well if everything was done, and you do not have any codes, then I suggest you re-calculate your MPG.

 

What do you mean by "everything"?

 

air filter-done
fuel filter-done
spark plugs-done
ks-done
PCV valve-done

what other things i should check/change

 

Oil change? Try cleaning your throttle body and check for any hidden codes (oxygen sensors in particular).

 

...

http://forums.maxima.org/showpost.ph...6&postcount=38

 

None of those things are going to get you 11.5MPG. What kind of driving are you doing? Something has to be seriously wrong if it's not all bumper to bumper driving. Like a leaking injector which should set a code.

 

Leaky injector wont 'leave' a code

 

so bad/leacky injector wont triger cel?

 

how about spark plugs i know i have ngk they usually last over 60k can they make such a difference?
another thing when i am driving over 50 my rpm dont go down they stay like at 3k-4k is that normal?

 

There are many factors to consider when it comes to MPG. General tune of car, tire pressure, hard acceleration (are you racing people from the light), high speeds (are you going over 70), extra cargo (do you have a big stereo or transport alot of people), what type of gas you use, are you driving into wind all the time, driving with the windows open?, heavier wheels.

 

i am gonna start with spark plugs and gonna work my way up i hope i get this thing fixed

 

Is your OD on or off . ..

 

is on why that makes a difference?

 

If it's off, it won shift into 4th, could be your RPM deal ...

 

what do you mean RPM deal?

 

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