Does the 3.0T have anti-drainback valves for the cam chain tensioners like previous generations? I am not sure. On previous generations when these valves start to leak you will get rattle on startup no matter what.
In general, for all VAG vehicles I've dealt with:
---Rattle will generally depend on how long the car has been sitting with longer periods of rest resulting in more rattle.
---Rattle will generally depend on precisely where the engine stops spinning, i.e. how much tension is on each particular valve spring and which direction this wants to force each cam to turn at rest. If it stops in one spot, you may get no rattle at startup even after a week or more of rest. In another spot, you may get rattle 4 hours later at startup.
---Rattle on some engines is strongly effected by drainback of the oil circuit, with drainback valve issues combined with stopping in a "louder" spot (as mentioned above) causing rattle to be extended past a second or two on a large portion of startups
---If you have an edge or other small piece broken off of a nylon guide, this may not affect the duration of the rattle, but will often affect the sound of the rattle, with broken guides generally resulting in a much more severe rattle which can still more or less go away after the tensioner is pumped up; I think many of us know what it sounds like when a large chunk of the guide breaks off causing the chain to contact the metal body of the guide assembly or the adjacent timing housing, that sound is unmistakable.
---In general, given the production of millions upon millions of engines, machining tolerances, vehicle to vehicle variance, the wide disparity in oil type, condition and environmental conditions, I begrudgingly agree with VAG that startup rattle should be considered normal. It doesn't sound good, but consider that there is no limit on the number of vehicles which have made this noise since early life and made it to 200k miles or more without a problem. One would think that installing a more granular ratcheting mechanism to the adjusters would solve this, but consider that due to the length of the chains you would end up in a situation where the chain shrinks on cooldown after a hot run; with excessive granularity in the ratcheting mechanism you risk ending up in a situation where the cooled timing components end up with a chain so tight that it actually breaks the plastic guides on startup. I'd rather have startup rattle than an excessively tight chain after a hot run in 0 degree weather followed by a cooldown to ambient temperature.
@WittyWookiee your mechanic in general is incorrect for this platform, you can replace the cam chain tensioners/guides with the engine in the vehicle and the only reason you'd be pulling the engine is to service the lower chain and guides which I have not seen to be necessary even on 3.2 FSI engines (very similar design) with over 200k miles/20 years on the original lower timing components. Certainly these engines must be getting to the age where the lower timing system service will become common, but I still rarely see it even with the age of some of these FSI vehicles.
@Spitfire007 I have never seen Liqui Moly or Pentosin result in any different oil usage than a "more cost effective" approved oil like Mobil 1 or Castrol unless a viscosity change was also involved. Since you are adding Lucas, this is the likely reason for a perceived change in oil consumption. However, I wouldn't add Lucas to anything, ever. That is an additive one dumps in a car they are trying to unload in order to temporarily conceal problems. The big concern with Lucas is that it appears to have an additive package similar to these "stop leak" products, and if you know anyone who has experience with these, they will tell you that they typically result in an initial reduction in leaking, followed by later leaking that is far worse than the original leak. I would never use any additive like this and in over 25 years of automotive service I have not seen a single long term benefit from such products, and have seen many drawbacks and problems created by them.
And in general... Re: Oil usage... 1 liter in 2500 miles? (I hereby excuse your mixing of SAE and Metric units)... I would like to point out that this rate of usage was almost universally considered normal not even 2 decades ago. A healthy engine *should* use oil. A little oil *should* be staying on the cylinder walls and getting burned during combustion. A little oil *should* be making it past the valve stem seals and slowly working its way down to the manifold ports. Etc. How else do things get lubricated? Imagine a perfect squeegee on a perfect windshield - That is NOT what we are going for with internal engine lubrication! For parts lubricated under pressure by the oil circuits, we depend on film strength, and for everything else we depend on surface roughness to carry some lubricating oil past the ring/seal/etc to keep things sliding smoothly. I wouldn't even begin to worry about a VAG engine until it started approaching a quart (ok, fine, a liter) in 1,000 miles - But in a 1L/1000mile case I still wouldn't worry one bit if it were a higher mileage engine! I intermittently service a colleagues old Daimler cars which have egregious oil usage due to prehistoric valve seals and other wear... We're talking 1 liter in 500-750 miles... And he just keeps driving these things, going for half a million miles. He refuses to even address the usage until he hits that mark xD
And finally... Re: Oil usage... Anyone who tells you their car uses "no oil" between changes... Is replenishing that oil with fuel that is leaking past the rings on cold starts, due to combustion issues, etc. If my car, regardless of whether it's one of my VAGs or my toyota V8, uses no oil - I immediately know something is not right! I will admit that some of these little rubber band engines (i.e. these little 1 liter fuel sippers in new cars) have a much lower rate of oil usage than larger and older engines, but even those must use oil. The only time I'm really concerned about oil usage is when I see the missing oil on the ground underneath the car.
Edit: One final note on the timing system: On all of these cars you can check timing advance from stretch in measuring blocks using VCDS (and surely OBDEleven though I don't use that product due to the subscription nonsense). If your values are within limits, literally the only reason you should worry is if the engine is so old that your timing guides may be brittle and close to breaking. My experience is at around the 15 year mark (regardless of mileage) the plastic guides are starting to become quite brittle and can be broken from one severe event (i.e. extreme subzero cold weather start, abusive/hard driving immediately after cold start, etc). If you are within limits and drive mildly, likely no reason to worry at all regardless of whether it rattles on every cold start or not. If you are within limits and don't abuse your car until the oil is HOT, still not much to worry about. If your guides are 15+ years old, regardless of mileage or whether you are within limits or not -> Let's just say you'll find out one day on a 10-degrees-below-zero cold start whether those upper guides have reached the point of being "catastrophically brittle" or not :-)
Originally Posted by NorthernGTI
I am a 034 nutswinger
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