Hey guys, So I recently bought an A3 Sportback and as I was buying it the owner said the engine rattles on a cold start. His father works in a car repair service and he said it isn't something bad. The guy drove the car and didn't see any problems with it, only the rattle on a cold start. I saw a thread here about the 1.4 TFSI, but I don't know how similar the engines are so I wanted to start a thread on my own. So I bought it, my father told me it isn't a big thing either but I read online about the timing chains being problematic and started worrying. How can I know for sure it is the timing chain? The car has good 170 000km and it hasn't been changed. I still haven't driven with it, but next week I will be able to use it and try to gather some more information. This happens only on a cold start. After that the engine rattles quietly. I changed the oil ( recommended oil from Audi ) and my father says I just have to drive a little bit so the oil starts running better. My father says this probably comes from the hydrotappers/hydraulic valve lifters ( sorry if it isn't right, im not that good with english car part names ). The guy hasn't changed the oil in quite some time I think, since it was really black and I think that could be the problem with the noises. So if the car gets good oil the noises should disappear (I think) I'm getting really worried since I don't know what this is and if the timing chain breaks my engine is going to say goodbye. I am going to gather more information, I could post a video with the sound if that is going to help. We still bought a timing chain and we're going to try and change it alone. But if the problem isn't the chain we are just going to postpone it until we can find somebody who does it for less money. Sorry if it's a dumb question guys, I'm new to cars but I find it really interesting. It's also my first car I have to take care of. Thanks.