PCV Delete in a 3.2 Carrera?

SkunkWorks · 12-08-2025, 02:13 PM

Is there any downside to deleting the PCV system in a 3.2 Carrera?

In the midst of refreshing all fuel lines, intake gaskets, vacuum hoses, etc. and figure I could just cap the 2 barbs on the TB related to the PCV and remove any chances of vacuum leaks from the system entirely if there's no real downside to doing so.

85RedCarrera · 85RedCarrera's Garage

I’d be more worried about any case pressure potentially pushing the rear main seal out.

brighton911 · 12-09-2025, 05:05 AM

I removed mine quite a few years ago and installed a catch can/separator in it's place (a must). With the lack of oil fumes being ingested, the intake and throttle body stay clean forever.

85RedCarrera · 85RedCarrera's Garage

Quote:

Originally Posted by brighton911

I removed mine quite a few years ago and installed a catch can/separator in it's place (a must). With the lack of oil fumes being ingested, the intake and throttle body stay clean forever.

The inside of my intake looked like it was used for plumbing at the La Brea Tar Pits...

I am interested in your catch can setup. We use them on aircraft. The tough part is figuring out how to vent the acidic vapors while allowing the oil to return to the case, without the vapor going in with it. Does your can have to be emptied, or does it return the oil to the engine?

SkunkWorks · 12-09-2025, 04:45 PM

Quote:

Originally Posted by brighton911

I removed mine quite a few years ago and installed a catch can/separator in it's place (a must). With the lack of oil fumes being ingested, the intake and throttle body stay clean forever.

Any pictures of it?

Sal corrected me on another group, I'm referring to the hoses and PCV valve for de-icing the throttle body.

Just seems like a lot of opportunity for vacuum leaks and car's in a garage so wouldn't see much cold usage.

ant7 · ant7's Garage

I have to say from my own understanding of this system, the main reason for it was to re-cycle crankcase breath into the inlet manifold, [sealed system] didn't realise it had a dual purpose.
I have recently changed the valve to a newer version that Porsche now supply as an alternative, its not a direct fitment, [have to modify the pipework slightly]but it works fine, IMO I wouldn't remove it, just fix what's wrong, and clean out the throttle body from time to time, but again, just my choice.
Ant.

mikedsilva · 12-10-2025, 02:22 AM

Quote:

Originally Posted by SkunkWorks

Any pictures of it?

Sal corrected me on another group, I'm referring to the hoses and PCV valve for de-icing the throttle body.

Just seems like a lot of opportunity for vacuum leaks and car's in a garage so wouldn't see much cold usage.

I have removed it from a few and seeing as I live in a relatively warm climate, the de-icing is never needed!
Cleans up a few hoses too.

As for the catch can, I've not found one that condenses the oil vapours back to a liquid fast enough, so my engine bay smells of 'hot oil'... maybe my rings need replacing..

wazzz · wazzz's Garage

I think the switch temperature threshold is about 10°C. Throttle icing can occur at temps above 0°C (32F) because of air speed and negative pressure. Don't know what the winter temps are like in Vancouver, probably not tropical.

brighton911 · 12-10-2025, 04:58 AM

Mine car is currently up in the air (on a lift for the winter) but I will be working on it soon and will post a pic of the system. I check the catch can at the end of the season and happily, no oil accumulations at all.

Tad240 · 12-10-2025, 05:15 AM

Can someone provide a schematic / diagram/ photos of the specific hoses and items that are being deleted / removed and / or modified? Sorry I’m a visual learner and I would also love to clean up this area if possible. Thanks.

brighton911 · 08:34 AM

Here are a few pics of the installation. The plumbing is as follows:
From the side port of catch can over to the oil filler neck and from the top of the can to that little plastic cup. There is never anything in the cup, it's a just in case. One could drill the tin and have the hose exit to the outside. As far as oily fumes in the engine bay, once I cured the blow by, there are virtually none. If your engine is producing some blow by, I would definitely plumb it to the outside. The large opening in the 90 degree throttle body rubber opening has to be well sealed as does the vacuum port on the throttle body and the PCV fitting on the oil filler neck too.

SkunkWorks · 12-10-2025, 10:21 AM

Quote:

Originally Posted by Tad240

Can someone provide a schematic / diagram/ photos of the specific hoses and items that are being deleted / removed and / or modified? Sorry I’m a visual learner and I would also love to clean up this area if possible. Thanks.

It's the PCV valve highlighted as well as the air valve (UFO saucer) and associated hoses that then connect to the throttle body. Compliments of GH85carrera:

C, D, and E here I believe.

Quote:

Originally Posted by wazzz

I think the switch temperature threshold is about 10°C. Throttle icing can occur at temps above 0°C (32F) because of air speed and negative pressure. Don't know what the winter temps are like in Vancouver, probably not tropical.

My car lives in a warm garage and never sees snow/salt usage. We're usually 0-5 degrees Celcius in the winter but again, likely won't be parked outside for much time on the cold days it does go out.

I did replace all the hoses and the PCV but am always itchy to decrease complexity and clutter from the car.