Hello all I posted this in a new members chat by accident

Recently purchased myself an Audi a5 45tfsi it drives beautifully from my perspective. Just had a major service with everything involved

However when it’s running and especially on cold starts i’ve noticed a strange ticking and knocking sound coming from somewhere in the engine. I would like to say it sounds non-metallic however I can’t be too sure. I’ve linked below a video I made if anyone would be able to give me an idea of what it could be I’ll be very grateful as I’ve just purchased the car. It does have 70k miles on it. Many thanks in advance!

Louis.

I suspect a loose timing chain, in which case I recommend you return it to the dealer within 30 days of purchase as it is an expensive job.

2 minutes ago, cliffcoggin said:

Louis.

I suspect a loose timing chain, in which case I recommend you return it to the dealer within 30 days of purchase as it is an expensive job.

Hi mate, thanks, what makes you suspect timing chain? It’ll be very unfortunate if it is the timing chain as it’s over 30 days since purchase. The garage I took it to did some scans and only found a faulty air circulation flap. Would a timing chain problem not be found on scanning diagnostics?

Cheers

21 hours ago, 45TFSI said:

Hi mate, thanks, what makes you suspect timing chain?

The sound.

21 hours ago, 45TFSI said:

Would a timing chain problem not be found on scanning diagnostics?

Not necessarily, if the crank or cam angle sensors are not detecting a change in relative positions. The chain tensioner could be worn enough to allow the chain to flop about without being loose enough to allow it to jump a sprocket tooth. It would be worth having it professionally inspected for reassurance.

20 minutes ago, cliffcoggin said:

The sound.

Not necessarily, if the crank or cam angle sensors are not detecting a change in relative positions. The chain tensioner could be worn enough to allow the chain to flop about without being loose enough to allow it to jump a sprocket tooth. It would be worth having it professionally inspected for reassurance.

I did have my uncle to listen he thinks it’s just a noisy engine with a loose aux belt.. if it was timing chain it would be a hard metallic heavy rattle within first few secs of cold start. I got another video of the sound when revving warm engine https://youtube.com/shorts/lSwRYQD5Jc4?si=pfqCTIWWvlzXhCGb

As you wish.