MK 6 R has a timing belt and normal water pump (or so it appears). So with that engine, is the only real PIA failure the rear seal? Other stuff would seem to be non-fatal and not that much work. That would assume the cam chain is prone to throwing a code before it grenades and it could be changed early. Is this summary pretty much true?
Yes and no.
The belt driven 2.0L turbo gas engines continued on after 2008 in certain models for a few years, the Audi A4, the Golf R, the Audi TT. These are akin to the BPY engine like the 2006/07/early '08 GTI/GLI/Eos/B6 Passat got. Those engines were largely still based on the "old" belt driven engines like the ALH/AEG/AWM/BEW/BRM/AZG/AVH/BEV/AWP, etc. The BPY etc. engines' early on had issues with the cam follower driving the HPFP wearing through, look similar to the PD cam/lifter wear, and like the PDs, made much, much worse by use of improper oil. However UNlike the PDs (or any of the VAG TDIs), oil consumption compounded this, something many VAG gas engines have had issues with. They did issue a revised camshaft and follower for these, which would have been factory installed on any of the belt driven 2.0L DI turbo engines after about 2008 (so all the belt driven Rs). And really, with those, so long as you use the proper 5w40 502.00 spec oil, good oil filters, and
keep it full, they are pretty robust engines. They also do not seem to have nearly as bad of an intake port gunking as the later DI engines for some reason. These use the same aluminum water pump inside the front of the block, driven by the timing belt, design as the other similar engines, a normal design rear main seal, etc. They had some sensor updates as well, mainly rail pressure sensors, as well as some lambda sensor issues.
The EA888 engines (the chain driven ones) can sometimes have plenty of timing chain warnings on the early ones, as the tensioners bleed down (there is a TSB for this, and an updated tensioner). However the later ones (2010+) already have the newer style tensioner, and they
can quite often come apart at cold start with absolutely no warning prior whatsoever. None. Some will exhibit CKP/CMP correlation DTCs and some noise shortly before, and those can be saved albeit it is still an expensive and labor intensive job. The timing chain design on these is unique, and by far one of the dumbest I have ever seen (and I have worked on chain driven OHCs on engines from Ford, GM, Toyota, Honda, Chrysler, Nissan, MB, BMW, and others). The crank sprocket does not index on to the crank with a conventional keyway or "D" shape, but instead uses this strange star gear thing that is difficult to describe. And it is not just one chain. There are three. One to run the camshafts, one to run the balance shafts, and one to run the oil pump. When you take the front pulley loose, the front sprocket has nothing to hold it tight to the crank, because it relies on the pulley for that. So it can jump off if you are not careful. It isn't like you can just expose the front of the engine and have the whole chain drive in front of you. There is an upper and lower cover. The mount is in the way on transverse applications, and the cam chain runs THROUGH the head. This is why it is an 8-hour job, even though it is done with the engine in the car (unlike the VR6 and I-5 engines that require transmission/engine separation) .
