[WOTMOTORSPORT]

I know this is common place upon cold start. 

 

Has anyone experienced this once the car is up to operating temperature? Similar to how it sounds once the downpipe has been changed. 

 

I have noticed the rattle/ticking is present when the car is up to temperature. The car is 100% standard. 

 

 

[T-800]

I know this is common place upon cold start.

Has anyone experienced this once the car is up to operating temperature? Similar to how it sounds once the downpipe has been changed.

I have noticed the rattle/ticking is present when the car is up to temperature. The car is 100% standard.

Now and again.

Mainly after driving away after it’s been stood for 1/2 hr or so.

Sounds like a faint echo of the start up noise if that makes any sense.

However.......now and again on cold starts mine doesn’t make the rattle noise at all.

Edited by T-800, 08 June 2018 - 08:07 PM.

[WOTMOTORSPORT]

Now and again.

Mainly after driving away after it’s been stood for 1/2 hr or so.

Sounds like a faint echo of the start up noise if that makes any sense.

However.......now and again on cold starts mine doesn’t make the rattle noise at all.

I have also noticed the rattle after the car has stood a short period. 

 

The rattle seems to persist regardless of temperature or driving mode. It is a slightly more muted rattle than that of a decatted car but loud enough to hear with the window down. 

[billymc92]

I have also noticed the rattle after the car has stood a short period.

The rattle seems to persist regardless of temperature or driving mode. It is a slightly more muted rattle than that of a decatted car but loud enough to hear with the window down.

Hopefully somebody takes it to Audi and the class it as a problem and fix it under warranty and then we would all have a solution for the problem

[T-800]

Hopefully somebody takes it to Audi and the class it as a problem and fix it under warranty and then we would all have a solution for the problem

What problem ?

[billymc92]

What problem ?

The ticking/rattling wastegate in the turbo

[T-800]

The ticking/rattling wastegate in the turbo

Don’t believe it is the wastegate myself.

Have held / moved the pivot/rod upon a cold start and the noise doesn’t change one bit.

Think about it logically.... if the pivot arm the the wastegate hinges on, is that loose that it rattles, why does applying hand pressure not stop it ?
More so why does pulling on the actuator rod to open the wastegate not stop it either ?


Have also recorded visually the wastegate actuator at cold start, it doesn’t move at all.

You’ve got to look at these things and see how they work before believing some twaddle that has been posted elsewhere.

Edited by T-800, 09 June 2018 - 12:41 PM.

[Fivepotfan]

I have also had a good poke about at the back of the engine during the cold start phase. I can concur with what T-800 has said regarding the wastegate. I grabbed the rod that controls the wastegate actuator and it does not move at all, however, I could use a bit of force to move it in and out by hand and it made no different to the noise.

 

With the bonnet up and your head positioned at the back of the engine above the turbo, it seems to me that the noise is actually being generated higher up somewhere above the turbo. If you grab the metal parts in this area (before they get too hot) you can feel the resonating/clattering through some of the components. I was wondering if it has something to do with the variable valve solenoids which are located in that area (I think T-800 has previously posted some images of these somewhere) and may be in a pre-programmed position during the cold start phase.

 

I have had the car for about a month now and I don't really notice it some much.......mainly because I have disconnected the exhaust valves and its fairly loud at cold start.

As all the FL cars appear to have the same trait, it's not something that is likely to be considered a fault by Audi. A classic example of the infamous phrase 'ah yes, they all do that sir'.

[seventeenapg]

Just a heads up from me, I have been driving my saloon for a week now and have covered a measly 250 miles so far. I have no ticking noise at start up so far.

[T-800]

Just a heads up from me, I have been driving my saloon for a week now and have covered a measly 250 miles so far. I have no ticking noise at start up so far.

I know some owners have reported it starting after a few hundred miles.

[T-800]

I have also had a good poke about at the back of the engine during the cold start phase. I can concur with what T-800 has said regarding the wastegate. I grabbed the rod that controls the wastegate actuator and it does not move at all, however, I could use a bit of force to move it in and out by hand and it made no different to the noise.

With the bonnet up and your head positioned at the back of the engine above the turbo, it seems to me that the noise is actually being generated higher up somewhere above the turbo. If you grab the metal parts in this area (before they get too hot) you can feel the resonating/clattering through some of the components. I was wondering if it has something to do with the variable valve solenoids which are located in that area (I think T-800 has previously posted some images of these somewhere) and may be in a pre-programmed position during the cold start phase.

I have had the car for about a month now and I don't really notice it some much.......mainly because I have disconnected the exhaust valves and its fairly loud at cold start.
As all the FL cars appear to have the same trait, it's not something that is likely to be considered a fault by Audi. A classic example of the infamous phrase 'ah yes, they all do that sir'.

I’m actually more inclined to agree with what we discussed on the dog and bone that time Brian....

That the new DAZA engine cold start involves a lot of engine retardation to get the cat heated up quickly, which would mean its running very rich, don’t forget this engine has 10 injectors now, it is using all 10 on cold start, coupled with the new solenoid actuated Exhaust valves timing.

If you listen very carefully on a cold start cycle you will hear at around the 20 sec Mark that there is a proper ‘shut off’ of the noise, like the ECU is saying ‘ok that’s that out of the way’

The faint rattle type noise people report hearing when the car is de-catted / not de-catted, is I think, still the exhaust variable timing/ injection process being used by the engine, but being ‘amplified’ by the exhaust system and being able to be heard about the engine note at low revs, you’ve got to remember this engine is nothing like the CEPA/CZGB replaces.... it does everything differently.

As Brian has said above, this engine won’t have been just ‘rolled’ out to the masses, ‘ala’ Focus RS scenario...

If you ever hear the B8.5 4.2 RS4 engine or the S6 4.0 twin turbo engine fire up on cold start you’d actually wonder what in tarnation was happening...........

[JayRS3]

10 injectors- damn!

[0120raptor]

I’m actually more inclined to agree with what we discussed on the dog and bone that time Brian....

That the new DAZA engine cold start involves a lot of engine retardation to get the cat heated up quickly, which would mean its running very rich, don’t forget this engine has 10 injectors now, it is using all 10 on cold start, coupled with the new solenoid actuated Exhaust valves timing.

If you listen very carefully on a cold start cycle you will hear at around the 20 sec Mark that there is a proper ‘shut off’ of the noise, like the ECU is saying ‘ok that’s that out of the way’

The faint rattle type noise people report hearing when the car is de-catted / not de-catted, is I think, still the exhaust variable timing/ injection process being used by the engine, but being ‘amplified’ by the exhaust system and being able to be heard about the engine note at low revs, you’ve got to remember this engine is nothing like the CEPA/CZGB replaces.... it does everything differently.

As Brian has said above, this engine won’t have been just ‘rolled’ out to the masses, ‘ala’ Focus RS scenario...

If you ever hear the B8.5 4.2 RS4 engine or the S6 4.0 twin turbo engine fire up on cold start you’d actually wonder what in tarnation was happening...........

I get the idea of heating the cats up quickly to reduce emissions but this is done as you say by running very rich. Rather defeats the objective of reducing emissions!!

[0120raptor]

10 injectors- damn!

Twice as many to go wrong.

[T-800]

Twice as many to go wrong.

Ever the optimist Neil.......

[seventeenapg]

I know some owners have reported it starting after a few hundred miles.

I'll keep an ear out lol. Hope it doesn't happen T but I guess there's a good chance it will!