New PCV Valve or Catch can?

[Wolfgang]

This afternoon my Golf gave the tell tale signs of PCV Valve failure by hunting from 800 - 1400rpm and not dropping below 1100rpm when comming to a stop. Kind of dissapointing seeing as it has under 30,000km on it.

My question is, should I just replace the PCV valve with an aftermarket or OEM item or install a catch can? Is a catch can worthwhile on a stock car or is a PCV valve good enough?

[Idle]

This afternoon my Golf gave the tell tale signs of PCV Valve failure by hunting from 800 - 1400rpm and not dropping below 1100rpm when comming to a stop. Kind of dissapointing seeing as it has under 30,000km on it.

My question is, should I just replace the PCV valve with an aftermarket or OEM item or install a catch can? Is a catch can worthwhile on a stock car or is a PCV valve good enough?

A catch can isn't a substitute for the PCV valve, and your problem isn't necessarily the PCV valve anyway — get it properly diagnosed before replacing anything.

[tom89]

Mine went at 60k a month or so ago. Needed the car for a drive to the snow a few days after so just slapped an oem pcv on it. I would have considered a catch can if I had time, I may still do so. I prevents oil and other crap from the crankcase entering your intake. I would say its worthwhile on a stock car but I'm pretty sure they are illegal.

Ive seen pics of guys emptying their CC after 5000km from new on an R and it was half full of oil!

FYI I had the exact symptoms you are describing. When it is playing up at idle try to pull the oil cap off. If its hard to do then it's most likely the pcv.

[Klink1313]

...........I would have considered a catch can if I had time, I may still do so. I prevents oil and other crap from the crankcase entering your intake. I would say its worthwhile on a stock car but I'm pretty sure they are illegal....

The catch can that I have is not illegal Ultimate Oil Catch Can . It does not vent to atmosphere and is connected back to the motor.

[Gigitt]

Catch cans are NOT illegal if they keep the system closed like the OEM system - back into the engine. All they do is filter/separate the vapour.
If you change the system to an open system ie: vent to atmosphere then you have just altered the emissions system and that is Illegal.

[Greg Roles]

Legality aside a vent to atmosphere is so smelly especially at the lights it makes you sick. I found that out by accident......NASTY!

[Wolfgang]

Thanks guys.

I will of course get it diagnosed properly first, just wanted to know my options so if it is the PCV I can get it fixed quickly becuase it is ****ting me to tears. Only does it when it's warm and is worse after I've given the car a bit of stick.

So the 42 Designs Ultimate and Stealth are both closed systems right?

[NabzGTI]

I've got the BSH stage 2+ catch can.. just be careful as there may be more work involved than you first think. In order to fit the catch can, I had to relocate the charcoal canister. These catch cans were designed for US spec cars where the charcoal canister is located elsewhere under the bonnet.

[bwen]

So the 42 Designs Ultimate and Stealth are both closed systems right?

Correct, both closed and designed to fit Australian delivered cars. There are quite a few places to mount them, with the most popular one being behind the passenger headlight, I've seen other people mounting it on the firewall with piping routed between the gap of the engine and battery box (underneath the intake).

[Wolfgang]

I've got the BSH stage 2+ catch can.. just be careful as there may be more work involved than you first think. In order to fit the catch can, I had to relocate the charcoal canister. These catch cans were designed for US spec cars where the charcoal canister is located elsewhere under the bonnet.

Correct, both closed and designed to fit Australian delivered cars. There are quite a few places to mount them, with the most popular one being behind the passenger headlight, I've seen other people mounting it on the firewall with piping routed between the gap of the engine and battery box (underneath the intake).

Thanks guys.

Hmmm... Sounds like a revised OEM PCV might be my best option as I want it fixed ASAP. After some reading it appears that it is hard to diagnose if the PCV has failed as the car throws a bunch of codes that has nothing to do with it. If it's going to cost me a similar amount to diagnose as putting a new one one there can't be any harm in just throwing a new one on as they are so prone to failure.

Rang McGrath Sutherland for a price, was directed to the wrong department twice, put on hold forever and then hung up on. FFS it's not that hard!

[Wolfgang]

Okay, so I have a new PC Valve (the parts department said "we go through heaps of them") in my possesion.

What I can't figure out is if I need a new breather hose as well? I can't find a clear answer.

[Wolfgang]

New PCV fitted today.

Feels better than ever.

[phillip1978]

Good choice on the OEM PCV

Here is a link to someone who has done a comparo between the OEM PCV and a catch can
result
worthless

Without/With Catch Can (Atmo) Comparison Pictures + Discussion - VW GTI Forum / VW Rabbit Forum / VW R32 Forum / VW Golf Forum - Golfmkv.com

[Greg Roles]

Good find, but you actually READ the thread? Most people including the thread starter agree with what has always been said, Catch Cans help REDUCE the problem, nothing cures it. Then other posters bring up the concepts of valve stem seals, turbo bearings - a lot is overlooked in your sweeping statement friend.

[Wolfgang]

I went OEM PCV simply for convenience, I needed the car fixed quickly and with minimal disruption.

An OEM PCV is more than adequate for a non modified car.

Drove down to GAD in Canberra and back to Sydney in one day, car ran better than I ever remember. It was the organic squishy thing behind the wheel that ddn't cope so well.