Need help! 2.0l tfsi blocked breather system..

[Black_Avant]

Basically my partner owns a 57 plate
Audi A4 2.0l TFSI petrol.

It keeps firing up P0171 fault code
"Bank 1, System too lean at idle"

I've already changed the main pcv valve on the top of the rocker cover. Knowing there is 2 types I've made sure it is defiantly the correct one.

The oil cap has a lot of vacuum and is difficult to remove and also vacuum coming through the dip stick tube when removed which both create the engine to hunt and run crap at idle.

The N80 valve seems to be working as it clicks when the car is running but I still seem to have in my opinion way too much vacuum in the crank case.

What the hell can this be? Is there anything else I could have missed, maybe someone's had the same fault but I'm running out of ideas. Non of the pipes that I can get too seem blocked and when removed the car runs crap so they all seem to be doing what they should.
Any ideas?

 

[maxdrz400]

Vag com is not my thing, but surely if your running too lean its likely to be sn injector/fuel pump issue. Checked your csm follower recently?
I get no fault codes and my car runs fine, and i also have a lot of vacuum on the oil system i believe its normal. Honestly sometimes its a struggle to undo the oil cap!

 

[Black_Avant]

Vag com is not my thing, but surely if your running too lean its likely to be sn injector/fuel pump issue. Checked your csm follower recently?
I get no fault codes and my car runs fine, and i also have a lot of vacuum on the oil system i believe its normal. Honestly sometimes its a struggle to undo the oil cap!

Yep, changed the fuel cam follower last week when I changed the pcv valve. Old one looked quite new but put the new one in while I was there.

I did notice there was no pressure when I tried to release the pressure from the "tyre valve" style pressure relief on the fuel pump. But when I disconnected the main fuel line going into the bottom of the pump it did have a normal amount of pressure. Not sure why it didn't release when I tried to let it out tho.

 

[Jack Kelly]

Have you changed the breather hose? I think it is a common fault and may be causing you issues, even if you can't see that it is damaged.

Sent from my Nexus 6P using Tapatalk

 

[Black_Avant]

Have you changed the breather hose? I think it is a common fault and may be causing you issues, even if you can't see that it is damaged.

Sent from my Nexus 6P using Tapatalk

Both breather hoses going to the pcv are sound. If you disconnect either end of both it runs rubbish. Clearly doing there job :/

 

[Black_Avant]

The main reason I'm looking at these issues are becuase my hand held brings up P0171 fault code, which many believe is the breather system at fault, my friends snapon system brings up P2187 "system to lean at idle"

I'm now wondering if the breather system is ok and that this is more of a fuelling issue..?

 

[jord9412]

i had same code for 5 month i changed the n80 valve which is a £20 part and it hasnt come on in 2 weeks so far.... not saying it will fix it for you but so far it has fixed it for me as the code would have normally come back on by now

 

[jord9412]

http://www.ebay.co.uk/itm/Bosch-028...e=STRK:MEBIDX:IT&_trksid=p2057872.m2749.l2649