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Discussion Starter · #1 ·
I replaced the PCV and N80, both were faulty. But when I try to pull off the oil cap now with an idling engine it is even harder than before. The engine does not run very different when I do.
  • Getting a P119A faulty fuel sensor code (Car Vista)
  • No or limited boost. Sometimes it does boost as it should for 1-2 days and then it's gone again most of the time
Would this hint towards a vacuum leak? I rechecked the all the hoses again best I could.
 

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2001 Amulet Red 225 coupe.Owned from new as well as a Nurburg VXR & an XR3, all from new.
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Hi, To test the DV, remove DV push & hold the piston/diaphram up & place finger over the vaccum connection, Piston/diaphragm should remain in posn & not drop.
Hoggy :)
 

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Discussion Starter · #6 · (Edited)
Thanks for the replies. Since the issue hasn't changed since before and after adding the new GFB Diverter Valve I assume it is not at fault. I have no way to easily get to it to test unfortunately.
What I was also wondering after reading so many contradicting messages on boards is the suction of the oil cap with a running engine. One side says it is normal and the other side says that and the dipstick shouldn't pull a strong vacuum. In my case the vacuum has only increased after replacing broken parts.

Replaced:
MAF, DV, PCV, N80
Carbon cleaning done

What I also found weird is that it ran perfectly fine for 3 days and then went back to low power/boost
 

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Mines doing this again, had PCV valve changed twice now, got better foe a bit then back to juddering. Had the dip stick replaced as the o ring seal was missing, that helped and now it’s back juddering again!
 

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2007 3.2 VR6 Roadster
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Unfortunately Carista is a generic OBDII scanner and is not designed for VAG software. Currently, both the Ross Tech VCDS and OBDeleven are coded specifically for VAG. You can still find the OBD fault codes by running a Google search for "Ross Tech xxxxx" where xxxxx is the fault code. The Ross Tech website will provide you with information on possible causes and solutions.

This post from the Knowledge Base is for the Evap faults, but may help point you in the right direction to resolve your current vacuum leak problems -
For more information on the OBDII readers, this post might be of interest -
 

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Discussion Starter · #9 ·
Unfortunately Carista is a generic OBDII scanner and is not designed for VAG software. Currently, both the Ross Tech VCDS and OBDeleven are coded specifically for VAG. You can still find the OBD fault codes by running a Google search for "Ross Tech xxxxx" where xxxxx is the fault code. The Ross Tech website will provide you with information on possible causes and solutions.

This post from the Knowledge Base is for the Evap faults, but may help point you in the right direction to resolve your current vacuum leak problems -
For more information on the OBDII readers, this post might be of interest -
Good content, thank you for sharing. Just to point back to the vacuum force experiencing on the oil lit? Is this normal to experience? I read everywhere this high crank case presure is terrible for your seals and engine so I am concerned driving around with it.

Cheers,
 

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t.rijnders87 said:
Replaced:
MAF, DV, PCV, N80
Carbon cleaning done
Did your problem start before or after you performed the carbon cleaning?
If it started after, I would suspect a bad / misaligned / reversed manifold gasket.

t.rijnders87 said:
I read everywhere this high crank case pressure is terrible for your seals and engine so I am concerned driving around with it.
It is true, high pressure is bad for your seals (one reason not to block off / delete your PCV valve) but your talking vacuum (negative pressure) not high pressure...
 

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The problen is your high pressure fuel sensor. If the sensor is reading low it will reduce the amount of fuel injected which will increase the vacuum to prevent the engine from stalling.

Bring it back to the shop who did the carbon cleaning.

Applying too much vacuum to the crankcase will starve your engine with oil.
 

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Discussion Starter · #13 ·
Did your problem start before or after you performed the carbon cleaning?
If it started after, I would suspect a bad / misaligned / reversed manifold gasket.

It is true, high pressure is bad for your seals (one reason not to block off / delete your PCV valve) but your talking vacuum (negative pressure) not high pressure...
The limited boost happened before as well. The tuner did a Vagcom read out and requested+delivered boost is correct he says. But on off days its just not pulling low down. Where before you could here and feel the car ran into boost and would pull hard from 2500-2800 onwards. This is most pronounced in 2nd gear.

Could it have to do with something like the valve timing or the N75 valve? I also hear a new whistle tone from 2k-3k RPM I am not sure was there before.

I took the risk of buying another new PCV and installed it myself. The high vacuum issue seems to be resolved. Oil cap now comes off without much effort. Unfortunately this did not result in better performance. But at least one less issue.

I have a recent new GFB diverter valve so I assume it won't be the issue?

In regards to the new fuel pressure sensor I will go ahead and order a new one. I did read this error can also be caused by the stage 1 tune?
 

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Discussion Starter · #14 ·
Maybe to add:
2nd gear boost only kick in 4K+ rpm. Before that the engine behaves and sounds unboosted
3rd gear 3.2K rpm
Higher gear up until 6 it gradually seems less of an issue

Power seems down about 20% and I don't feel the same "tension". Could there be such as thing as an occasional boost leak?
 
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