A8 cam chain tensioner
 

I have a 2001 Audi A8 with AUX engine code. I have removed the passenger side valve cover and found that the cam chain tensioner is broken. Can I remove the cams and replace the tensioner with the head still on the car? Should I do the same to the other side? I have the Bently repair manual and it mentions a special tool to lock the tensioner. Can I do the job without that tool? I have done several cylinder head repairs on 4 and 5 cylinder models but never on this V8.

I did it on a A8 2004 same engine 4.2 V8, the new tension-er came with the tool attached. There is already a write up on this site for changing that part. I only did the broken one as its quite expensive part.

Can Tensioner
 

The tensioner is rather pricey so how is it broken ? No,
l don't believe replacing it without the locking tool is
possible unless maybe you'd use a couple zip ties. lf
you'd do the other side is up to you and your wallet.
Timewise, l'd say at least lift the valve cover so you
can see what's going on - usually what's happening
or happened on one side is equal to what's happening
or happened on the other side. The heads can be
left on the car, no problem. Actually this engine, to be
a V8, is very simple to work on especially with the
Bentley. l have no hesitation is working on it, its very
nicely built and designed. Unfortunately l've bent
valves TWICE !! :( !! The first time due to being lazy n
not lifting the valve cover and checking things out and
then the second time mysteriously the belt snapped.
Now, obviously, l'm trying to take every precaution to
make sure things are good in all areas.
l should recommend: Don't be, do not be ! lazy in this
area - really take your time and be thorough, when the
job is complete you will have taken proper measures
to ensure everything is good on parts, timing, cleanli
ness, specifications and so on. When all is put back
in place and you're wheeling the the blvd. you won't
have any question in your mind about how good
everything is - you'll have peace of mind.

Bent Valves?
 

I turned the engine to TDC and it looks like the intake cam has slipped one tooth on the chain. The chain and sprocket look ok but I can't tell if this changed the timing enough to blend a valve. Is there a simple way to tell?

compression test is pretty easy