PTC Nipple removal and cleaning

[Michael Dixon]

DGM,

Thanks a ton. Have resolved to do the entire job at once.

I will post my results.

Mike

[DGM]

DGM,

Thanks a ton. Have resolved to do the entire job at once.

I will post my results.

Mike

Good for you. On the long run you will save.

Replacing a RMS (rear main seal) is time consuming and expensive .

[matthew1]

Looks like it's my time for a PCV job. Last done on my 850 in 2007, roughly 30k miles ago.

Here's my PTC nipple cleaning photos from last night, halfway through the cleaning + my new elbow solution (3/8ths Gates rubber heavy vacuum hose) already applied:


Worn, broken elbow next to it.


A little brush to get inside the housing is ideal. That and parts cleaner of whatever type.


It got it off and back on without taking off the intake tube.

[jblackburn]

It got it off and back on without taking off the intake tube.

You've got smaller hands and/or more patience than I do!

[rmorse]

What I'm confused about it how Matt did all that work with only getting ONE finger dirty...

[matthew1]

What I'm confused about it how Matt did all that work with only getting ONE finger dirty...

There's a hole in the finger of one glove.

[Power Jets]

I've read through the discussions, but is there resolution on the functionality of the "PTC Nipple"?

From the photos I see a metal aperture restricting the PCV flow to the inlet manifold and a vacuum connection. A vacuum driven valve? (perhaps to prevent PCV backflow contaminating the mass flow sensor during idle). Or maybe the vacuum connection is achieving something similar by scavenging the flow when idled.... if so there would be gunk up the vacuum tube? Or maybe just a vacuum pickup to drive something else?

So, does anyone have a definitive theory of operation? Thanks!

[jblackburn]

The intake side of the turbocharger provides vacuum (to the PCV box) when there IS no vacuum from the intake manifold because positive pressure is being forced through by the turbo.

When the turbo is not boosting (e.g. idle), the small vacuum line provides vacuum to that area directly from the intake manifold.

[Power Jets]

John, thanks, I should have been explicit... mine is NA but the principle is likely identical.

So the vacuum line is actually extracting PCV gas from the throttle region when the car is at idle, and is thus prone to blockage. I'm thinking about increasing the diameter of the vacuum line to delay the onset of blockage and reduce idle pressure build up.

Makes sense? Thanks!

[jblackburn]

On an NA, the small vacuum line simply adds vacuum to the area when the throttle body plate is closed at idle.