Now that I have the 2.0t FSI BPY engine over 100k miles I figured I would put together a conglomeration of what I have learned over the years to keep this engine running well. I love this engine and despite some common issues it truly is an unbelievable performer. I will break down each one of the problems and include what I believe is the best way to handle it. This is for the 2.0t FSI BPY engine specifically commonly found in 2005.5-2007.5 North American MK5 GTI, GLI, and some Jetta’s. This is also a high-level overview where I won’t go into too much detail. If you have any questions feel free to add a common or message me.
Please note that I do modify this engine and some fixes will be third-party products and not OEM (Original Equipment Manufacturer).
Positive Crankcase Ventilation (PCV) system:
Over the years VAG (Volkswagen Automotive Group) has released countless updates to the PCV valves in this motor all of which still seem to fail over time, even with stock setups. Symptoms of a failed PCV valve include loss of pressure (boost) in the PCV system. This is also a symptom of a failed Diverter Valve (see below for more information). If one of your PCV valves is to blame it is most likely your front PCV valve that has failed. This is pictured in Figure 1 above. The rear one is right below the MAF on the backside of the engine. The rear PCV is actually inside a metal tube called the breather tube.
The solution is to either replace the valve with the latest version and wait for it to break again or get a PCV block off plate. The PCV block-off plate removes the front check valve entirely and replaces it with a machined plate thus eliminating the potential of its braking. I purchased one of the BSH catch can kits which also includes one of these plates. This kit also solves other issues which you will read about below. Here is a link to BSH that offers a few PCV fixes BSHspeedshop
Before I got the BSH fix I had a different attempt by Eurojet. Their solution was to add another check valve on top of the failure-prone one. This is the silicon tube with the billet check valve coming off of the front PCV valve in figure 1. This did an OK job but really only masked the issue and didn’t solve it well.
Engine valve buildup:
Because of the way the 2.0t FSI’s fuel injection works the gunk can build up over time on the valves by oil and junk flowing through the PCV system to the valves. to the left is a picture of what valves can look like over time.
Loss in performance is a sign that this might be happening. But that is also a very vague sign that could be the result of a lot of things.
If you already have buildup the best way to resolve it is to take it apart and clean it. This is a very time-consuming task or expensive if you have a shop to do it. You could try using a cleaning solution like Seafoam or BG Induction Cleaning that doesn’t require taking everything apart.
To prevent buildup it is a good idea to install a catch can. This will catch the foreign contaminates in the PCV system before they get to the valves. You will need to empty the catch can every so often. A good time is when you do your oil changes.
The 2.0t engine has been known to consume a lot of oil in between oil changes. VW says you should change your oil every 10k miles but also says oil consumption less than 1qt every 1k miles is acceptable. In other words, they will only start to replace things under warranty if you are consuming more than 1qt of oil per 1000 miles.
The resolution is to check the pistons and cylinders to make sure they are still round and sealing correctly. The other thing to do is install the latest rings, which seem to help with sealing better. I have not gone to these extremes to check for this as my consumption is closer to 1qt every 3.5k miles. Because of this I do my oil changes every 5K miles instead of the recommended 10k and check my oil level twice between oil changes. Typically I add another 1qt between oil changes.
High-Pressure Fuel Pump (HPFP), cam follower, and cam:
The HPFP has been known to “drill” right through the cam follower right into the cam itself. This can cause a very expensive repair bill to fix the cam, cam follower, and HPFP. There is a lot of speculation as to what causes this issue and how to prevent it. Design, oil consumption, oil type, performance software, Reversion “A” cam being soft, early version HPFP, are all factors in these speculations. Some of the signs that you may be having problems with cam follower wear are fuel cuts and poor performance when lots of fuel is being used. Here is an example of a cam follower that had been punched through by the HPFP.
I have not had this issue and I have a few ideas as to why. Since I have owned the car I have been running one software performance profile or another and do not believe it is related to this failure. I also am running the original HPFP and reversion “A” cam that came on the car. I believe I have avoided this issue by performing oil changes every 5k miles, topping off oil between changes, and using an oil that contains a higher amount of zink which can help with metal wear. The oil I have been using is Castor Syntec 5w40 for almost all my oil changes. This is the oil that dealers will typically use and is VW 502 certified. For a list of approved oils check this PDF here It is a good practice to check your cam follower every 20k miles for signs of wear and replace as necessary.
VAG just recently extended the warranty of these three parts to 120k miles.
As with some VAG engines the coil packs have gone through many reversions and even a recall. Signs that your coil packs are failing include misfires, and poor idling.
I have all four of my coil packs replaced by the dealer under a recall. They were not showing any signs of having a problem, it was just part of the recall. I was well out of warranty and did not pay a cent to have them replaced since this was a recall.
The early diverter valves were prone to failing. The diaphragm on the diverter valve is made out of rubber and can tear. When it tears air that is supposed to be held for pressure for your turbo escapes causing performance loss and sometimes a CEL in more extreme cases. Common signs of this will be loss of pressure (boost) in the turbo system. A common CEL code for this is P0299.
VAG switched from a diaphragm diverter valve to a piston-style diverter valve on its D reversion of the diverter valve. This solved the tearing issue and has been rock solid for me and a lot of others. Other third-party diverter valves such as Forge will fix the problem but required more than just replacing the valve to implement and are not electronically actuated like the OEM one. As of the writing of this page, the latest version of the OEM diverter valve with the piston is 06H 145 710 D. I also have a guide on how to replace it here: How to replace your diverter valve
This is a silly design idea VW had with the GTI and GLI where they routed noise from the turbo/intercooler system into the cabin of the car. You also get a very slight performance loss due to this. You can see the noise pipe in figure 1 above.
Commonly people either plug the hole on the charge pipe or replace the pipe with either an aftermarket part or the one from the Audi S3 which does not have the extra outlet for the noise pipe.
Air Condition Compressor:
The early air condition compressors have a habit of exploding and sending debris through the AC system. When this happens your compressor, condenser, expansion valve and a bunch of misc parts need to be replaced as well as the system flushed the debris.
I only have a theory on how to prevent this since it has not happened since my last incident. Turning off your AC and letting everything spin down before shutting off the car is my idea on how to prevent this. It could also have been the latest compressor that solved the problem.
Oil filter housing:
The oil filter housing is plastic and it is very easy to crack by over-tightening or not taking it off correctly. Recently a metal version of the housing has come on the market by a third party and although this sounds like a nice solution it only causes a higher chance of stripping the plastic threads where it screws onto.
I have a guide on oil changes here that give you some tips on how not to break it: How to change the oil on the mkv fsi engine
Taking off the Engine Cover:
The engine cover is also your car’s intake. Trying to take it off incorrectly can crack or break it causing your intake not to function correctly. This can lead to performance issues and CEL’s (check engine lights)
Here is a guide on how to take it off properly and make it easier the next time you take it off: How to take off the 2.0t fsi engine cover