[RO55]

Hi everyone!

First Post, I wish it would have been more light hearted but I'm in a bit of a pickle, I've recently bought my dream car, Audi S5 V8 but once the engine has warmed up properly I've got this horrible rattling noise from behind the left wheel, and it's freaking me out that it could be the timing chain.

I've done my research and whatnot, most but not all people say that the b8 s5's don't have the same problem with the timing chain as the older B7 RS4, and should last the life of the car? but I'd just like to make sure.

If I've done this right, a video should be attached? And FYI the car has done 99k miles so far.

Thanks much in advance Video

 

[Dan1845]

Hi everyone!

First Post, I wish it would have been more light hearted but I'm in a bit of a pickle, I've recently bought my dream car, Audi S5 V8 but once the engine has warmed up properly I've got this horrible rattling noise from behind the left wheel, and it's freaking me out that it could be the timing chain.

I've done my research and whatnot, most but not all people say that the b8 s5's don't have the same problem with the timing chain as the older B7 RS4, and should last the life of the car? but I'd just like to make sure.

If I've done this right, a video should be attached? And FYI the car has done 99k miles so far.

Thanks much in advance Video

I’m FAR from an expert and will await the ones who are to also comment but it does sound potentially like the timing chain. Is this the first you’ve heard the noise or gradually gotten worse over time?

Again let’s await the people who know to comment as I’m more than happy to be wrong 🙂

 

[RO55]

Thanks for your input, as I mentioned, I recently bought the car but with no rattle at all, the car has been sitting a few weeks while I get insurance/tax sorted which I'm not sure would change anything?

I also have access to VCDS if anything can be done on there.

 

[findalex]

Start with VCDS to check for codes on both the engine and transmission modules. If you have the original VCDS, you can post your autoscan file on their support forum and they'll have more experience interpreting the error codes.

The timing chain stretch rattling is usually worse at cold start since there isn't enough oil pressure for the tensioner to properly tension the chains. So if your rattling gets worse as the car warms up, it could be something else.

There are also a lot of other chains (e.g. for the oil pump, balance shaft, etc.) that could be rattling due to stretching, tensioner, or chain guides failing.

Hopefully you've caught this early enough to prevent further major damage.

 

[RO55]

Thank you for the reply, I've had a really good dig into the codes and output tests/monitoring for the car today, in fact. There is only one code for the engine and that's an "air intake switch-over valve no communication", (I have no clue what that is) unfortunately the VCDS I have is really really old (windows XP old) but still scan properly so I'm not sure how to approach them with it. As you mentioned about the warming up, the noise is worse the warmer the engine gets, and there is no noise at all or on startup. it goes from not audible unless you have your head inside the engine bay on startup to hearing it a good 12 feet away once up to temperature.

That's an amazing point though about warming up, it even has me wondering if it's even in the engine or just a loose bolt or heat shield etc, I've asked a few mechanics in my area and they've all turned their noses up due to having to drop the engine to even look at it... and possibly being an Audi and don't want to touch it just in case 😂. if it is the timing chain it might have to be an Audi job, which has my wallet feeling light just thinking about it.

Again thanks for your help, it has slightly put my mind at ease and given me some hope... 🤞

 

[findalex]

A quick search of "air intake switch-over..." points to a disconnected sensor on the air intake filter box or something like that. It's probably not related to the rattling.

You'll most likely have to take off quite a few things to get to the rattling part (whatever it is). If you have the tools, you can take off the wheel closest to the sound and try to pinpoint the source. You can use a car stethoscope or just use a big screw driver and put the handle against your ear.

I'm sure you'll find a good-hearted indy mechanic who is willing to help. My experience with U.S. dealerships is that they always write up a lot unnecessary work even when you pay them for the diagnostic.

 

[SimonRoma]

Mate you need to visit a good VAG specialist NOT stealer. This really could be anything but is NOT likely to be the timing chain I think cos they rattle from cold and then go quiet as the engine warms up so dont worry too much lol.

 

[RO55]

Thanks for all the inputs, I'm in the UK myself and I've only found one mechanic that's even willing to look at the noise, I'm keeping my fingers crossed and hopefully my next post will be showing off the car instead