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Anyone Considered Venting their PCV System

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RyanGLT
Posts: 185
Joined: 6 November 2010
Year and Model: '07 XC90 V8 AWD
Location: Topeka, KS

Re: Anyone Considered Venting their PCV System

Post by RyanGLT »

to the best of my knowledge, it is illegal everywhere in the US unless you have a vintage car that come STOCK with no PCV.
'07 XC90 V8 AWD

boosted5cyl
Posts: 1100
Joined: 29 January 2010
Year and Model: '98 V70 T5, '99 S80
Location: St. Paul, MN
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Post by boosted5cyl »

'04 XC90 2.5T AWD (Angus) 134K.
'99 S80 T6 (Medusa) 214k. On borrowed time LOL
'98 V70 T5 (Vivienne). RIP @ 228K. Spun rod bearings.

BRONCMAN
Posts: 24
Joined: 7 February 2011
Year and Model: 1998 S70 T-5 auto
Location: Idaho

Post by BRONCMAN »

Ive got a new pcv kit from ipd, but if it wont set any cel's then I think I might just vent mine. I seen the hose that goes to my ptc(turbo model) from the pcv is broken to all hell & was basically plugged. The system would have been replaced by now, except that I have caught a flu bug or something & have been too sick to work on the car. Rather than replace the whole system & continue to feed my engine all its own crap, Id rather put an end to these problems & help my engine as well. Does anyone know if you can run the car without the ptc valve in place because I would like to get rid of it & replace the whole intake hose?

BRONCMAN
Posts: 24
Joined: 7 February 2011
Year and Model: 1998 S70 T-5 auto
Location: Idaho

Post by BRONCMAN »

Anybody know if you can disconnect the ptc valve with no problems?

jblackburn
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Post by jblackburn »

My thinking is that it would crap oil all over the inside of your intercooler lines, and then all that oil would either drip out the bottom (like mine is currently doing) or be burned in the engine through the intake valves rather than being separated out and put back into the crankcase. I think a system like this is actually mostly necessary on a turbo car.

As I understand the system, it creates a big vacuum above idle on that valve that sucks that oil that gets past the turbo seals into the box and puts it back into the oil pan. At idle, the small vacuum line sucks the vapors (since there is not much oil) directly into the intake manifold.

Someone feel free to correct me if I'm wrong about that - that is just how I understood it to work as I was taking it apart.
'98 S70 T5
2016 Chevy Cruze Premier


A learning experience is one of those things that says, "You know that thing you just did? Don't do that."

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Henry10
Posts: 2
Joined: 21 October 2010
Year and Model: 1995 850 Turbo SW
Location: NYC

Post by Henry10 »

PTC is a dual device:

1- PTC heater
2- PCV Valve.

You can do without # 1 function, but not without # 2, unless you love doing rear main seals every second day... Whether you vent into the atmosphere or into the intake, the crankcase needs to exhale, simple as that.

The solution is clean the oil separator and/or install a catch-can (if your car is a turbo).

Ozark Lee
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Post by Ozark Lee »

Disconnecting the PTC will result in a vacuum leak and a subsequent CEL at the best or a massive oil dump at the worst. If the PTC is the problem just clean it. If the oil trap is clogged deal with that before you blow a RMS.

...Lee
'94 850 N/A 5 speed
'96 Platinum Edition Turbo
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1999 V70XC - Nautic Blue - Totaled while parked.
1999 V70XC - RIP - Wrecked Parts Car.
1998 S70 T5
1996 850 N/A
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