2006 BUL engine sounds

[CroftyOriginal]

I know there are quite a few threads on this already so I apologise in advance but I have just bought an A4 B7 2.0 TFSI and you guessed it, it sounds like a diesel, I dont know the condition of the cam follower so I have gone ahead and ordered one to be on the safe side, I know the injectors can sounds ticky also but I don't want the timing chain to give out on me, is there an easy way to see if I should do the timing chain and tensioner? Its on 90,000 miles. Also is there anything else I should look out for or get done for peace of mind?

 

[AudiB720TS]

is there anything else I should look out for or get done for peace of mind?

You should also consider what oil you are using, and how much there is in the engine.

Apart from the cam follower, the 2006 also has a "bad" cam shaft -it was revised in a later year to incorporate a harder metal.
Ideally, when replacing the cam follower you should also inspect and possibly replace the cam shaft, but that's a nightmare so try the other stuff first.
On one of my old cars, I did a kerosene flush to remove deposits and that really helped with valve train noise (bucket tappets / hydraulic lifters, assuming Audi uses those).

 

[Charlie Farley]

The " BUL " code engine had revised camshaft lobes in 2006 year of manufacture aswell , it was non " BUL" engines that had soft cheese cams that were later replaced with harder ones.
My 2006 BUL has never suffered with cam follower issues , but then the BUL engine is the best of the bunch anyway.

 

[AudiB720TS]

it was non " BUL" engines that had soft cheese cams that were later replaced with harder ones.

How sure are you about that statement?
When I upgraded my fuel pump, because of the warnings that Autotech (HPFP) puts on their packaging, I tracked down the Audi (USA) recall statements and compared to my VIN number / engine code. Accordingly, my engine (BUL) would be affected. I have a European 2006 manufacture, model year 2007. I would assume that if US cars were affected then so would European cars. Unlike say, BMW, Audi did not build cars in the USA for that market.

 

[Charlie Farley]

I have a late 2006 BUL engine and it was not effected , and had the revised cam fitted from the factory.
The BUL did have a few issues at the very start of its life along with the other engines but most issues were quickly resolved, you can tell the early engines visually by the cam cover, they were silver in color whereas the later ones are black, I think you'll find that European 2006 and beyond all came with the harder cams , I woud'nt like to say about US spec cars as they seem to have had more recalls than European varaints.
The lobe still wears but its a much more manageable situation.

 

[Charlie Farley]

Cam follower wear.
The main weak spot is the cam follower located below the high pressure mechanical fuel pump. it has a low friction coating on it a bit like "Teflon". The follower resembles a thimble that sits on the bottom of the fuel pump. Check this every few years or at 30,000 miles for wear.
This fault was altered in later models with a different cam lobe set up, for example the 220bhp BUL engines are not affected by this issue. You are looking out for the coating wearing off, if it has worn down and exposes a metal surface this causes very quick wear through the follower and damages the cam shaft. The first you'll know about it is in lost fuel pump pressure and a check engine warning light coming on. It is a simple check that most drivers can perform. Be very careful about the extremely high fuel pump pressures and ensure the pressure is released from the system, a jet of fuel at this pressure could potentially a cause major injur

 

[CroftyOriginal]

Quick update, just been to a few garages and no one wants to do it, I found an Audi and VW garage by the off chance hidden away in an industrial estate and they are saying the BUL engine is belt driven with a chain linking the cams, I was quoted £350 including parts, water pump and labor.

 

[Charlie Farley]

The rear cam chain links the inlet and exh cams, the problem can arise from the tensioner which then causes the chain and sprockets to wear and it all needs replacing.

The tensioner is hydraulic so if the oil ways get clogged the tensioner doesn't work properly and you get all the subsequent probs.
I have said it a fair few times, the long life service schedule kills these engines, it's the root cause of most engine failures etc.
10k between oil services maximum really.

 

[CroftyOriginal]

The rear cam chain links the inlet and exh cams, the problem can arise from the tensioner which then causes the chain and sprockets to wear and it all needs replacing.

The tensioner is hydraulic so if the oil ways get clogged the tensioner doesn't work properly and you get all the subsequent probs.
I have said it a fair few times, the long life service schedule kills these engines, it's the root cause of most engine failures etc.
10k between oil services maximum really.

How hard is it to replace that on your own without going to a garage? If its even possible.

 

[Charlie Farley]

Its very doable but think about tackling it first as its not really an easy one as space at the back of the head is very limited , you need a few special tools aswell if you want to do it properly and not botch it.
If you do it yourself you will save a fair few pounds in labour cost, but, you may want to offset that saving by getting a garage to do it and save you the hassle.
I'm doing mine very soon and have already purchased the cam holding tools and special splined bit to do the job , just waiting to do a few other jobs on the engine in that area to save doubling up on things.

 

[i3oricua]

https://www.audizine.com/forum/showt...d-the-problem-

Give this a look first before you start tearing the back off the engine. Very easy know if it's messed up.