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Ok, so I've had the car for just over a week now and have a question (probably a stupid one but I'll ask anyway!)

When driving the car there is a whining noise from the engine that matches the revs. It's nothing to do with transmission as it's there when the car is revved standing still. Best way to describe it is like a hydraulic power steering whine, belt rub or water pump/alternator bearing issue. It's noticeable from inside the car particularly when pulling away and there's no road noise but not so noticeable to cause immediate concern. So popped the bonnet for the first time tonight and gave it a few revs and with the bonnet up the noise was more noticeable. Also the engine sounded quite tappety, somehow I expected a smoother sound from the V8.

I haven't driven any other RS4's so have nothing to compare it with so wondered if any of you guys/gals have the same noise? Or am I looking at a warranty call for a belt, waterpump bearing-esque type failure? Would also appreciate thoughts/comments on how tapperty your engine is. There's only 10.6k on the clock and it's just been through the pre-purchase service and Audi used car check (for what that's worth!).

Also when you blip the throttle how responsive is it on your car? When doing the above rev tests mine seemed to rev ok then dwell very slightly before returning to idle slower than expected with a couple of burbles from the exhaust on the overrun(this is in comparison to the Exige). Again not what I expected with this type of fuel injection.

It's probably just me with the new car paranoia with all the new noises to get used to but though I'd ask anyway

Cheers

The 'tappety' noise you refer to is the cacophony of fuel injectors - in this engine each is triggered each time it fires the fuel in, so you will hear what should be more of a constant 'ticking'. Correct? It's normal.

The 'whine' - yes there is one with this engine. Many engines with long and large poly-V belts can tend to do this due to the several items being engine driven, and the idler pulleys necessary. Large alternators will contribute, as will engine-driven hydraulic fluid pumps. Listen to an E46 M3 - same issue.

The 'blip test' - it's a 4.2 litre V8 with a large flywheel, and a whole host of engine management which will manipulate fuel cut-off and air injection on lift-off.

Sounds like you have a healthy child...

And welcome to the fold.

The engine appears to be a very durable part of this car. Apparently elements of it were designed to permit even higher revving (9k)...

Sorry, yes, and chain-driven cams can be a bit whiney too. And, i think i read somewhere, notably where there's gear that varies the valve timing.

Cheers, I thought it would just be the normal new car paranoia

I wondered what those noises were myself !
Helpful and informative replys as usual... Thanks

rjkflyer wrote:Many engines with long and large poly-V belts can tend to do this due to the several items being engine driven, and the idler pulleys necessary. Large alternators will contribute, as will engine-driven hydraulic fluid pumps

you guys really blow my mind with depth of your knowledge, great having access to it.

The whine on the S4 and RS4 is due to the large duplex timing chains on our engines - there's a photo somewhere of the engine in the factory and IIRC there's 5 large timing chains on the back of the engine.

The dwell on blipping is a deliberate policy that the engine management implements - it does two things; first it stops the engine revs dipping and then recovering (remember what used to happen with carburettors?), and it reduces emissions. Most engine management systems cut fuel completely when the revs are above about 1500rpm and the throttle is in the rest position.

I sit in my car and pretend/wish that the whine was a supercharger....

Will

Porky wrote:I sit in my car and pretend/wish that the whine was a supercharger....

So far the only supercharger kit offered for the RS4 is rumoured to cause the engine to fail after only a few huindred miles....

Here's what your new baby should sound like ... "perfect"...


http://www.youtube.com/watch?v=vfEZJ5vjsU4

I know it's a bit lame but the 'unique sound' ad was the beginning of the slippery slope for me....before I'd even seen an RS4 for real

The rough part is, when you're inside you're insulated from it quite abit. Though sport mode and low revs is quite a rumble