2009 C30 Volvo -- Intake manifold leak w/ loud sound

[C30Vehicle]

Hello,

According to my mechanic, my 2009 C30 Volvo with 81k miles is experiencing an intake manifold vacuum-leak (that is too much air is being sucked-in; hence, the engine is running too lean). The 'Check-Engine' light is on (the readout code is P0171).

The intake manifold increasingly emits noise when engine temperatures increase. My mechanic says this is uncommon for C30 models.

What is likely involved in repairs?

Thank-you

[kmason1296]

Once it starts making the noise, try pulling the oil dipstick. If the noise stops it is a oil trap leak. Some bladder in there makes the noise when the pressure increases. My volvo dealer says driving it that way won't hurt anything in the short term. It is just annoying as all get out. My 2011 T5 C30 has 95,000K. I have maintained meticulously, but I just developed the problem. It is presently being replaced. PCV Breather System Kit for the the C30. I am also preemptively replacing the timing belt as I fully intend to drive my black beauty another 100K. I absolutely love my C30..

[Dreadvolvo]

I have a 2005 s40 and it is making the exact noise, pulled dipstick out and noice went away. Right now I am trying to get the air out of the system by keeping the oil filler cap slightly open. If anyone has any suggestions please let me know because the vacuum will only continue to pull up through dipstick and oil filler.