Audi S4 exhaust valves

[Hydracam]

Morning all.

I've just bought an Audi S4 Avant and I noticed there are valves on the rear exhaust sections. I also noticed that on another thread about the RS4 exhaust it was mentioned that they opened when the sport mode was selected. Is this the case for the S4 aswell and what do they do...?


Paul

[T89 Callan]

There is no sport mode is there?????

Mine is a manual and doesn't have sport mode but still has the exhaist valves.

Anyway as I understand they open at certain rpms and engine loads whenever you are driving to improve top end performance.

[Tame Technician]

The above is spot on, They open themselves (no button) at higher rpm and throttle openings. This is to indeed to improve performance, and to make sure it passes the EU noise test (done at lesser throttle openings/rpm)

Best left alone, unless it really bothers you, then you can jam them open for a bit more noise. If you do mess with them make sure the vacuum hoses are sealed/plugged or the engines other vacuum actuators wont work properly as the vacuum all leaks out.

[Hydracam]

Sorry guys I should have mentioned mines the B7 S4 with the Tiptronic auto gearbox. This has the sport mode which seems to sharpen up the throttle and turns it into a 5 speed box. Just wondering if the valves wher like the ones on the RS4 they where talking about on another thread.
Thanks for the info though it's makes sense.


Paul

[Tame Technician]

Your sport button is only for the auto box.

But yes the valves are basically the same as the RS4, R32, TT3.2 etc.

[Hydracam]

Thanks for your information guys. TT I have another issue. Just after I bought the car I got Audi to put it up on the ramp and show me aroundd under the car. One of the things noticed was the leaking rocker cover gaskets which I was told is not uncommon. They also quoted me £300 to replace them and clean up the sides of the engine. Part of me doesnt want oil dribling down the engine but is it going to cause a problem with the alternator etc...



Paul

[Tame Technician]

Hydracam said:

Thanks for your information guys. TT I have another issue. Just after I bought the car I got Audi to put it up on the ramp and show me aroundd under the car. One of the things noticed was the leaking rocker cover gaskets which I was told is not uncommon. They also quoted me £300 to replace them and clean up the sides of the engine. Part of me doesnt want oil dribling down the engine but is it going to cause a problem with the alternator etc...



Paul

Dont really understand why they want to charge you to fix it if you got it from an Audi dealer (used car warranty?)

Unless its pooring out highly unlikely to cause any problems to have a minor oil leak from the cam covers, many V6's and V8's do.

Thought they had the sealed water cooled alternator, so virtually imposible to get any oil in there at all.

[Hydracam]

I bought the car from an indipendant dealer and just wanted for my own piece of mind to have an Audi Technician have a good look at the car an let me know about any possible issues. Interesting about the water cooled alternator. What about the exhaust manifolds, any danger of the oil flashing...?

[Tame Technician]

Never seen it, Oil never well very rarly clatches fire on road car manifolds, maybe the odd tuned turbo motor. In realety, worst case senario it smells bad and smokes a bit. But has to be a really bad leak for that to be noticable.