# Horrible MPG!!! 95 maxima 277,000 miles on car.



## fd757 (Sep 18, 2015)

Great car, 277,000 miles on the car. Mileage is suffering. 18 mpg in city. Should it be getting more? Can the O2 sensor be suffering my MPG's? How hard is it to change the spark plugs on this car? Thank you for any input!


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## Happymax (Aug 14, 2013)

fd757 said:


> Great car, 277,000 miles on the car. Mileage is suffering. 18 mpg in city. Should it be getting more? Can the O2 sensor be suffering my MPG's? How hard is it to change the spark plugs on this car? Thank you for any input!


Have you run some injector cleaning fluid in your gas? Those O2 sensor codes are a sham,i have had one from a check engine light checking, for three years with no change in my gas mileage.
I have a very low mileage 98 Maxima bought new and today going on 30K i just get around 16 mpg, and would be happy with 18mpg.

Maye if plugs are really old that would be a start,but 277K is a lot of miles so spending a lot of money to get a little better gas mileage is not a good idea.


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## fgalvan84 (Apr 29, 2016)

It could be the o2 censor but your check engine light would be on. Yes MPG would be terrible with a bad o2 censor due to burning rich fuel. To much gas going to your engine, you may even smell gas sometimes. 

Get a code reader and hook it up if you have check engine light on. Go to Autozone they do it for free, just be careful your not getting stored codes. Be sure there current Atuozone has a stronger code reader they use to erase stored codes from ECM. You drive your car for a while, and if anything is malfunctioning relating to thr engine the check engine light will apear with your current problem code.

If it's the o2 censor check the harness with a multimeter 1st, to make sure your getting voltage from the batt. Then check your censor itself. If it's a bad connection due to wiring issue that's an easy fix, just peel back then reconnect with wire tape, Atuo zone will assist with that. If it's a bad censor just replace.You can look up vids on u tube for help. Just remember there are different types of o2 censors in your car, it's really easy to change, finding the location is the challenge, but Atuozone will help. Good luck.


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