Hello eveybody,i need some help with my Max.It's giving me very bad mileage like 12.5 miles per galon!I have changed the fuel filter,air filter and O2 sensor but nothing.Does the ECU needs some time to get used to the new sensor?I diconected the battery for more than 12hrs,that should be enough to reset it right?Any sugestions will be greatly apreciated.

 

Under inflated tires, maybe.

 

Nope,the presure is ok.

 

Nope,the presure is ok.

 

I've also heard that bad catalitic converters can cause poor fuel mileage. Have you gotten it checked out?

 

I don't think so but my muffler went bad last week.

 

I would check with your local Nissan dealer just to see what they recommend. Or if you have a personal mechanic of your preference. Could be, but I'm trying to avoid fuel injectors because they are expensive to replace.

 

The post before yours suggested the cat. converter may have gone bad. And now you say your muffler had gone bad.
I think the bad converter may be the problem because if it is not doing its job i think the muffler takes a beating from the chemicals that are not taken care of by the converter. So if you take a bad muffler and poor gas milage into account together, i would say the cause of both would be the converter.

If you will have that checked also consider that something may have also caused the converter to go bad (ie poor combustion overloads the exhaust, or whatever) Basically, just be cautious because any problem in a car may have another problem that caused it.

Good luck!