Hi Everyone, I have a 2001 Dodge Durango with the 4.7 in it. It had always gotten between 13 and 16 MPG but over the cuorse of the last few months it has dropped down to 8 MPG consistently. Now this has been a bullet proof vehicle, it has well over 200K on it right now and I know the motor is getting tired. It burns oil but is still a very reliable truck.

I can assume some of the basic tune up stuff, plugs, filters, etc. But does anyone know of any type of sensor that might cause such a sudden decrease in gas mileage?

thanks.

 

I will move this thread to the first generation Durango section,
FF

 

02 sensor could be bad, it would be the precat sensor, and yes they can go bad w/o throwing a code. OEM sensors only for replacement

 

+1

Sounds like a pre-CAT sensor.


Could also be spark plugs (doubtful), replace with Champion Copper (yes the cheap ones) and gap at .040 before install.

 

Like said above I would replace the O2 sensor as well as doing your full tune up. This includes replacing the plugs with Champion Copper (CHEAP), replace the air filter or clean it if you have a K&N (or equivalent), and clean out the throttle body and IAC port.

 

+1 on that!

Don't forget to reset your PCM! https://dodgeforum.com/forum/1st-gen...ine-light.html