The CEL came on so I pulled the code P0170 from my wife's V40 and the reader said "system too lean Bank 1".

Can someone tell me what is causing this lean condition?

MAF sensor?

O2 sensor?

Vacuum leak?

 

I also have same code on my 2005 s40.
did you figure out what it could be? car is burning gas like crazy.
the check engine light comes and goes after a few starts.
not sure what to do.. a mechanic might just scam me into changing random crap that doesn't need changing. i know almost nothing about volvo's setup

 

It was over 3 years ago but I think it was a vacuum hose.

 

thank you for the reply. I'll have a look to see if any of them are the culprit / leaking. I was also told to change the fuel filter since that may be the cause for the excessive fuel consumption. i think the car wouldn't give me even 500km to a full tank. probably 400 at the rate i see the needle drop.

happy 2014!