[Kidzor04]

Hi guys, i am getting 18 mpg (13 L/100km) i just drive to work and back 17.5 miles 90% on motroway but something doesn't match i work 6 days a week so in total there are 315 miles driven with a full i have for like a week and half, so is 500 km divided by 60 L (full reservoir) that means 8.3 L /100 km is this the right way to calculate?

I connected an OBD and i found problems with Lamda sensors and Nox can this be the problem ?
What else is affecting the fuel economy?

my car is 320i e93 2007

[Tambohamilton]

Those problems certainly wouldn't help. I suggest you get that sorted out, then see how your fuel economy is.

[Keith325i]

Originally Posted by Kidzor04

Hi guys, i am getting 18 mpg (13 L/100km) i just drive to work and back 17.5 miles 90% on motroway but something doesn't match i work 6 days a week so in total there are 315 miles driven with a full i have for like a week and half, so is 500 km divided by 60 L (full reservoir) that means 8.3 L /100 km is this the right way to calculate?

I connected an OBD and i found problems with Lamda sensors and Nox can this be the problem ?
What else is affecting the fuel economy?

my car is 320i e93 2007

Not sure if you got this fixed or not but anyways.

I presume you have the N43 engine as you mentioned nox codes. Your nox sensor is dead. I had the same problem with my N53 engine when I bought my car (Nox, lambda etc). You can either buy a replacement or order an emulator (what I did - check out bimmerprofs).
Basically, what happens is when the sensor fails, the engine will not use stratified charge (eco mode) in order to protect the Nox converter. When you replace the sensor, the engine will resume using the stratified mode and your mpg will improve.

I went from 28mpg to 35mpg.

[Black_325i]

I have 17 mpg (UK) on my 325i N52

[Phil325i]

Originally Posted by Black_325i

I have 17 mpg (UK) on my 325i N52

Wow, unless you drive it everywhere like you stole it, you must have serious engine issues to get consumption that high.

[Black_325i]

Nab I don't drive fast and only been in ds 4 times in 2 years not my type to mess with sport mode and manual stuff I like running things to keep running without issues, its 108k miles looking for a upgrade 😄

[s5s]

I just replaced the NOX sensor on a 330i 2009 with N53 manual. Before the repair, I had ~ 28mpg. After the repair, I get ~ 30mpg. That's from the trip computer over 100miles or so and that was mostly motorway driving. My car is also a lot less responsive and feels less powerful - this is to be understood. But if I could choose - I'd take 2mpg less for all the responsiveness and power I had before. Let's see - maybe my mpg goes up with time. Next are oxygen sensors.

[dephrank]

I think you can map the sensors out so the problem is never happening again, ever. Happy driving days.

Or go with Noxem from bimmerprofs.