Rattling / Grunting Noise Coming From Engine

[TomT23]

Hi,

I have a 2010 A5 2.0 TDI Convertible.

I have a strange rattling / grunting noise coming from my engine. I'm not quite sure how to describe it.

What is strange is that the noise only happens when I let off the accelerator. It seems to happen at lower speeds. (But perhaps that might just be because there's less road noise...)

What is even stranger is the noise completely stops as soon as the car is stand still.

The noise doesn't happen when I accelerate. However, perhaps it does but the engine noise made from accelerating covers it up...

I have a feeling the noise is coming from the driver's side of the engine (mines a right-hand drive, for anyone outside of the UK!). Although that might just be because I sit on that side...

I've attached a video where you can hear the noise. Unfortunately, the road noise makes it difficult to hear it. But I hope it helps.

If anyone might be able to tell me what the issue might be, that would be much appreciated.

I look forward to hearing your thoughts.

Thanks,

Tom

IMG_5266.MP4

[Steve Q]

Welcome to the forum Tom :) 

You'll find the members on here are a friendly and helpful bunch :) 

What's the mileage on your a5? 

My first port of call would be to have a diagnostic check carried out to see what fault codes (if any) crop up. 

I'm wondering if this could be a turbo issue? 

Is there any loss of power at all?

Cheers

Steve 

[TomT23]

Hi Steve, 

thanks for your reply.

its got 84k miles.

yes, I need to get that done. This week the engine/emissions warning light came on. However the noise has been going on for quite some time before the light came on...

i have no issues with power.

When you say a turbo issue, that scares me quite a bit! Would you suggest not to drive it at all?

If it helps, it hasn't had a new cambelt and water pump done yet. Given the age and mileage I think it's about time I had it done. Don't suppose that could cause the noise and the warning light?

i look forward to your reply.

thanks,

Tom

[Steve Q]

32 minutes ago, TomT23 said:

Hi Steve, 

thanks for your reply.

its got 84k miles.

yes, I need to get that done. This week the engine/emissions warning light came on. However the noise has been going on for quite some time before the light came on...

i have no issues with power.

When you say a turbo issue, that scares me quite a bit! Would you suggest not to drive it at all?

If it helps, it hasn't had a new cambelt and water pump done yet. Given the age and mileage I think it's about time I had it done. Don't suppose that could cause the noise and the warning light?

i look forward to your reply.

thanks,

Tom

Hi Tom its definitely due a cambelt and water pump change. 

Sorry, I'v not meant to scare you and to be fair I could be making a star in the dark with that to be honest. I suggest this due to the noise occurring when you let off the accelerator. 

The rattle could also be a failing engine mount? I had that on my a6 and the rattle was caused by a broken engine mount.

If the emissions light has come on then this could be due to a failing dpf or egr or at a guess an issue with glow plugs or maybe injectors. 

I'd definitely get a diagnostic check done. If it helps your local Audi will offer a free health check but obviously this won't include the diagnostic check which I suspect will cost around £60.

Sorry I can't help more, 

Cheers

Steve 

[Dan3222]

As Mr Q has said don't be scared, even if it is the turbo on its way out the car will drop into limp mode, pull over and stop the engine, switch it back on and it should drive as normal for a while. That's a worse case scenario though mate.

there is a good chance the emissions warning light coming on is linked, this is actually potentially good news because the ECU should have logged a fault, so when you get it scanned it should point you in the right direction. However my stab in the dark is the intercooler is on its way out!?! Not betting on it though..