Posted for a friend:
I have had a 2000 maxima se for over a year now. the car was a gift from my older brother as he did not need it anymore. the car had been sitting for a few months and needed work. we had a tune up done and multiple coils replaced. ever since getting the car, i have had terrible gas mileage. so i decided to replace 3 oxygen sensors and put a new catalyctic converter on. this still has not helped. as of the other day, i got 60 miles on what was said to be 6 gallons of gas. i should be getting double that. so any suggestions anyone?

 

Have you checked for a dragging caliper? After sitting for several months that could be a cause?


What about the airfilter?

 

What is its function?

 

wait for it...

 

OAN: i highly doubt a dragging caliper would for one..cause 10mpg and two if it WERE that severe, you would see/feel that whatever caliper that is thats bringing your mpg down by AT LEAST 10mpg.

are there any symptoms, SES lights or anything going on with the car we should know about? and how long have YOU (owner of the 5th gen) been driving this car/tanks of gas have you gone through??

 

Does the car feel weak during acceleration? Got any check engine lights illuminated?

 

^
Check for a knock sensor code. They dont fire an ses light.

 

Oh yeah, his rear or 2nd cat is also bad. He only puts in $5-10 of gas in everytime he fills it up.

 

$10 will give you only @3 gals...

 

No but he really does get bad mileage. He's filled it up to the top and barely gotten around 100 miles. And he drives hella slow

 

KS won't even give you mileage like that unless you're WOT 100% of the time.

KS + MAF on the other hand...

 

what is he using to measure mpg?

if i read it right he is getting 100 miles to the tankfull???

geez i get roughly 100 miles on about 1/4 tank +/-, but i got a 5 speed and drive slllooowwww.....



now you said he got a tune-up? NGK's? oil change? what type of fuel? 87 octane? 89 octane? 93 octane?

the fuel map is determined by the engine computer on our cars, so iuf he has new coil packs & new plugs then thats really all is needed. unless there is something wrong with the car that is causing it to dump fuel.

by any chance has he checked for intake leaks or is he blowing black smoke from the tailpipe ( good indicator of running rich=dumping fuel )

 

89 octane, sorry i should be more specific when I say around 100;150 miles total, yeah I know that's a huge difference but around 100 is what he said. He never goes over 2k rpms. Its an auto