Hello,

I bought my 07 530i with 98k. Recently and have been getting a P0171 or P2096 fault constantly. I'm very new to these bmw's and work as a bmw tech at an independent shop for almost a year. So this code is for bank 1 only. trying to understand how only bank 1 can be lean. when i first got the code, first thing i did was replace the pre-cat O2 sensor. code stayed off for almost 2 weeks and came back. I than brought the car to my shop and used our smoke machine to find any leaks. No leaks anywhere were found. Car runs good and averages 24mpg. Did some research and couple guys in the shop said its possible it could be MAF sensor. For some reason i thought you got a fault for the MAF if that was bad but if its not working just right i guess it could fault for just 1 bank. So just yesterday I replaced the MAF. Code came back next day. SO...

Possiby bad DISA valve?
exhaust leak between o2 and manifold to head?
bad or clogged injector?

 

does the car burn oil at all? could be contaminating the o2 sensor.

or i'd guess a intake leak which is resulting in too much air, not enough fuel.

 

Car runs good. No burning of any oil. No weird idles. I thought an air leak originally but an air leak at the throttle body, intake boots or vacuum lines usually USUALLY give mixture or lean codes for both banks, not just one. Thought maybe a fuel filter but again i see that causing a lean condition for all cylinders.

 

I had a 04 530 with all the same codes and looks like ur replacing everything I did o2 sensor mtf cam shafts sensors.. later after 1k I found our it was the manifold adjuster unit
It has a like flap tha opens and closes well the flap breaks and sure enough that what it was it cost me about 140. It slides right in like a ink cartridges on a office copier

 

I think you are describing the DISA valve.

 

Well I'm looking at it now and it's the manifold adjuster unit. I was throwing lean codes o2 sensor codes camshaft sensor and maf codes and misfiring codes bought all new stuff only to find out it was the manifold adjuster flap was cracked off on one side.. I had no more codes after that. But I sold the car now I have a 550i

 

But yes aka: DISA valve

 

Where did you purchase the new DISA valve from?

 

I went on the net and Google it then I price checked a bunch of sites and got one for $145.00 brand new

 

Thanks man! I'm definitely going to search thenext because I'm getting the same thing but also for bank 2