Testing PCV Valve for Failure & Cam Follower Pic
 

decided to do a bunch of maintenance today on my A4. Everything from changing the oil, checking the high pressure fuel pump cam follower (I highly recommend doing this!), checking PCV valve, and switching over to my winter wheels.

I check my cam follower every 2 to 3 oil changes (30,000 to 45,000 kms). This is what mine looked like after 45,000 kms. I keep an extra one on hand if needed. I installed a new one since I didn't like the look of this one.

My idle hasn't been great for a while now, so I decided to check the pcv valve since they are notorious for failing. I did a bunch of searching on the net and found tons of conflicting and confusing info about how to test the PCV valve - i.e oil cap test....should there be suction or not, and how much should there be...lol

The PCV valve is easy to remove so I took it off and did the blow and suck test. Sure enough I was able to blow passed the check valve even though I could hear it moving into place. Since the thing has multiple ports I wasn't sure if the check valve blocks all of them. Searching the net for clarification wasn't to helpful either. So i decided to buy a brand new one and replace it anyway.

So for the record if others are trying to decide if their PCV valve is shot or not...Absolutely no air should blow pass the check valve. you can suck air, but you will not be able to blow air through the valve since the check valve blocks it. With the new PCV valve installed my car runs much better.

BTW I had NO CEL light with the bad PCV installed. And both old and new PCV valves are the latest "P" version. Obviously even the latest P version still fail after time. So don't assume yours is good just because it's the latest version. It's extremely easy to remove and check....so forget trying the oil fill cap test. Totally inconclusive in my opinion! I'll now be checking it when ever I check my CAM follower.

Next job - cleaning the intake ports! My car has 280,000 KMS so it isn't going to be pretty! yikes lol.

Also, I used the tags shown in the picture whenever I switch wheels. Keeps them clearly labelled so I can rotate them properly next season. Tire-Tags.com if you're interested in some.

https://www.audiforum.ca/attachment....ine=1446330923

Re: Testing PCV Valve for Failure & Cam Follower Pic
 

I just changed mine - having a slight hesitation issue from 0-50 - it's an 06 with 180K. Got the part from AA Auto. they look identical and have the same part number. But with the new PCV on the car almost stalls - like it's starving for air - put the old one back on - problem solved. Will try dealer - or the blow test - thanks!