Happy New Year everybody! 2012 is here and it’s going to be a good one!
Just a few quick updates for this post…
First things first, sorry for the extreme lack of updates, the MKV front is getting a little older and a little quieter. That’s alright though, the MKV generation of cars has been holding up pretty well. The FSI follower problem has been troublesome for a lucky few and there are various small sensor/peripheral problems (thrust sensor, low pressure fuel pump, pcv and diverter valves etc.) that owners have had to deal with but overall, the cars have been robust. Maintenance just needs to be kept up to date. I recently rolled past 108,000 miles and the car runs great.
Still coming for the month of January:
The recently mentioned aftermarket cam follower is still awaiting final finishing but the company states that it should be released as soon as this month. This follower is supposed to provide 3x the life of the OEM follower by using a different surface treatment (hard chroming). If the product lives up to its promises, FSI owners can rest just a little bit easier about their cam follower issues.
The Koni Yellow Dampers are holding up well and I think I finally got the rebound settings perfect for the stock springs. When you have adjustable dampers, it’s almost impossible to just pick a setting and not fiddle with them. They tempt you at every corner. I’ll do a write up with the settings soon.
I recently received a letter from Volkswagen of America stating that the warranty for the pcv valve and intake manifold motor has been extended to 10 years/120,000 miles. You will also be eligible for reimbursement if you paid for repairs on any of these parts. Signs of pcv failure may include loss of boost pressure, poor idling and sometimes oil being pushed out of the oil cap. Intake manifold failure usually results in poor cold starting and sluggish low end performance. Either case can also cause the check engine light to come on.
I’ll upload the document as soon as I can scan it in. Here we go.
I opened up my non-functional revision G pcv valve and took a few pictures, enjoy.
In my current quest to return some parts back to OEM spec, I’ve recently purchased the latest revision PCV components. The latest revision PCV valve is “P” with the part number 06F129101P. There is also another revision of the rear breather tube, part number 06F103215B. The valves in the latest revisions seem much stronger compared to my old “G” revision. The check valves are now spring loaded instead of free moving. I don’t know when they switched to the spring loaded valves because I completely skipped over the 2 or 3 other revisions.
If you’re wondering why I went back to stock, I wanted to remove the catchcan I’ve been running. An intake manifold teardown by a forum member revealed that catch cans do little to aid in preventing the intake valve deposits inherent to direct injection engines. I have also been thinking about the lack of intake vacuum working on the crankcase. In the catch can setups, vacuum is sourced from intake air moving over the rear breather tube exit. I think it is a max of 3″ of mercury according to BSH and this occurs in the higher rpms under boost. At lower rpms, actual vacuum may be much lower. Too little flow or stagnant flow through the valve cover may allow the blow-by gasses to start forming deposits. I’ve noticed a little grime building up around the oil cap area, despite the regular oil changes. The accumulation of these blow by gasses can contaminate oil and deteriorate it much faster as well. Another side effect of routing all gasses through the rear breather tube seems to be, ironically, more oil in the charge pipes. If a recirculation type catch can does not catch all the vapors, the rest end up condensing in charge pipes and intercooler. The stock system sends them directly to the intake manifold to be burned off. The way the stock system works, it only reroutes vapors through the charge piping and intercooler under boost. When I installed my throttle pipe, a good amount of oil came pouring out of the pipes.
Now oil vapor in the in the intake charge is detrimental to performance. This is where a catch can does help. Oil vapor can effectively reduce the octane level of the intake charge and lead to more knock, which would then decrease performance. I haven’t noticed a performance difference since I switched back to the stock system but then again, my car isn’t exactly a horsepower monster. It is a compromise situation but after many miles of thought, I’d rather have the stock system deal with the evacuation of the crankcase gasses. The stock pcv system flows a lot and I don’t think some of the catch cans flow enough.
The stock pcv valves have not been models of reliability, which is one of the reasons catch catch cans have sold so well. Modified and stock cars alike can blow through them. These newer parts are now several revisions deep and they seem to be much more robust pieces. The rear check valve in the breather tube looks much better. The front pcv check valves have a more positive engagement compared to the “G” revision I compared it to. I guess only time will tell!
The 2.0T FSI’s pcv system has gone through several revision changes. Earlier valves failed rather easily, causing boost pressure to creep into the crankcase. Checkvalves would leak and pressure diaphragms would rip. Symptoms include oil coming out of the valve cover gaskets or oil cap, reduced gas mileage and power or increased oil consumption. An unsteady idle is another symptom and severe cases will cause a code to be set. This latest one seems to be a bit more robust than previous versions. The check valves are spring loaded now instead of free floating for more positive engagement. If you want to stay stock here are the latest part numbers.
The latest pcv system part numbers are 06F129101P for the front pcv valve and 06F103215B for the rear breather tube with check valve. The 06F129101P part number only works on rear breather tubes that have a built in check valve. Certain VIN’s / model years have breather tubes that do not have rear check valves. The only way to be sure it to pull it off and check for the valve. Here’s some excellent information for replacing the PCV valve and breather tube. The link also shows the Eurojet check valve solution so just ignore it if you are not going that route.
This is the Eurojet PCV solution. It is essentially two pieces of silicon with a machined aluminum check valve. The check valve ensures that boost does not leak out of the intake manifold and into the crank case. It also supplements the stock check valve. It does what it needs to without any frills. However, the flow of the check valve is not really known. The stock pcv valve goes from open to closed with hardly any pressure. Eurojet’s valve is stiffer. I’m not saying that this is necessarily a problem but it is different from the oem valve’s operation. For those who want a pcv fix that allows the pcv to function as intended (route crankcase vapors to the intake under vacuum) this is the fix. Volkswagen has released newer, updated revisions of the oem pcv valve but failures can still occur under higher than stock boost levels.
I still feel that the newer catch can solutions are still your best bet for fixing boost leaks involving the pcv system. It’s a little more maintenance (having to empty the can out) but it helps keep the intake tract a little cleaner.