I have a 04 Max I use to get 23.6 mpg. Two of my Three catalyst converters went. I had them replaced i also had a tune-up done with Nissan spark plugs (suppose) I now get 17.3-18.6 MPG any ideas or solutions.
Thanks

 

Not sure if it will help that much but when I put a performace exhaust on my 08 I think my mpg's went up a mile or two. Nothing crazy but better than nothing. I do about 19-20 now if I drive it like a normal human, which is rare! haha good luck bud

 

Damn.....I get 25.7 all the time combined city and highway from almost 3 years constantly. How do you guys get that low? Something needs to get it fixed.

 

I always get 14mpg in city and 25 on highway. I drive normally, thats the price to own a 250+hp car

 

Were the spark plugs pre gapped or ensured they were gapped properly? Also did you ever have a CEL for the 02 sensor when your cats were failing?

 

Check your O2 sensors. I consistently get 23 24 on the turn pike and 16 to 20 city. I'm always in the pedal though. And rowing thru the gears tiptronically

 

Just wondering if some of these MPG variations are not due to temperature.

This year has been worst then other years for anyone in the Northern to Central parts of North America.

In Manitoba we have had temperatures in the mid -20'C to -35'C for the last 2 Months so my gas Milage is also low. City about 16 MPG and Highway combined about 20 MPG. Have not had an opportunity to do too much Highway driving yet.

Have only had my 04 Maxima for 4 months so no clue what it will do when the weather warms up.

Nice to have the Average MPG display on the Dash Screen but wish we had the option to have a display for Instantaneous MPG as well as Average.

 

Yeah, I consistently get 16-17mpg city this winter. When it's warmer like summer time I get around 20mpg city. This winter has been cold and temps up and down, plus my car hates the ethanol rich winter blends of gas we have now. Highway I get around 22-23mpg right now, on a long trip.

This is with new OEM coils, new ngk iridium plugs and everything tip top shape, car tuned no problems, no codes, and only 90k on the clock so I think it's normal mpg. And that's on the vq30 where you guys with the vq35 and heavier 6th gen bodies should really have even worse mpg! And I have full intake/exhaust/gutted cats and EMU so those things don't really improve your mpg.

 

I heard mpg increase with font size used

 

I was getting about 18 and then I got a k&n intake and magna flow catback and improved to 20 mpg in city. Try a fuel system cleaning too.

 

I get 13 in my H3 and 18 in the Camaro if that makes you feel better

 

This polar vortex has robbed my MPG this winter.

 

Am on my third Cat... if you replaced the Cat, then you should also replace the O2 Sensors......Bad Cat will burn the Sensors = poor MPG.


Add Sea Foam to tank on full up... add all about 200 miles before oil change. Change Air filter, plugs, PVC (mostly neglected item)...


I get 24 mpg on summer.... 23 in winter.....