Hi,
This is my first post. I bought an RS5 2011 recently and a few days ago I noticed a strange sound. There are no errors on the engine after scanning with VCDS.
I attach here the video, maybe someone recognises it. It comes more from the left side of the engine.
Thank you
Maybe if you can get a better sound clip as it sounds pretty normal to me. Injectors are fairly loud and can sound like ticking lifters.
Thanks for the answer. I have made another video today, hope it is better. I will take the car for investigations as there is a strange sound also at slow accelerations, it can be heared on the recording too.
Sounds completely normal until you give it a little gas, almost sounds like one cylinder is missing or you have a bearing issue.
Being that I’ve had an engine with a spun rod bearing I’d say it sounds almost similar. A scary statement but until it gets looked at I wouldnt’ drive it. If that is the problem the crank maybe saved if caught early. I’d get an Oil sample to an Oil analysis company right away. That will tell you if there is an increase of certain metals (Iron for sure). With that said there is always the chance it’s just a bad lifter or High Pressure fuel pump or follower which definitely is less of an issue. Hard to diagnose from the video though.
Hi, thanks for the answers, indeed it is bad, but I don’t know how bad.
There were small pieces of iron in the oil and the mechanic decided to take the engine out. The most probable cause is a broken rod that impacted the crankshaft. At the moment the engine is out but not yet disassembled so I don’t know yet the exact issue. I hope I won’t need another engine 
Sorry to hear that for sure. I would guess that it is/was a Rod large end bearing that failed and/or causing the rod to possibly fail. Will the engine still turn over? I’ve got two engines with failed Rod large end bearing failures. One I believe was due to oil contamination and/or poor oil quality/change intervals. The other was a low mileage engine that had been pulled from a wrecked car and stored for a couple of years and initially had some water mixed with the oil in the crankcase from condensation/intrusion associated with poor storage, all flushed before initial startup after install but it only lasted about 300mi before bearing failure. I’ve read about a few other similar failures which shows a weakpoint possibly but not a widespread problem as their are a lot of these motors in RS5’s & RS4’s out there. I do suggest using a top quality oil and changing it much more often than Audi’s Stupid 10k mi/15k kilometer interval.
The engine was running ok, just like you see in the video. It did not lock, just that there was this extra noise. I will let you know what was the issue once I find out. I got the car 3 months ago, and to my knowledge, the oil has been changed in time, but it has 176k km so I think it might be because of usage. I think it was a bit abused. However, I paid 23k on it so I was expecting some issues, but … maybe not so serious. Any idea what else I can do since the engine is out? I was thinking to remove the cats, but I don’t know how to do this. Do they just get cut off? or do I also need some other updates to avoid errors?
Where are you located? If you’re in Europe I see a lot of Engine rebuilders for the CFSA engine on Ebay.de Not cheap but not too bad if you’re looking for a zero time rebuild motor for the most part. I’d just check into feedback/reviews for the various ones. Wish we had that availability in N. America, the CFSA was only available here in the RS5 for 3 yrs so there is no rebuild knowledge here and almost no place will touch the motor unless you bring them suitcases full of cash and they’d be learing as they go. In the UK, I think MRC does a Catless mod to the stock headers which is what JHM does over here and works well. If they do your motor then a Waterpump/Thermostat and housing replacement for sure and might consider a new A/C compressor. The AC compressor is a Nissans unit, search a replacement by the Nissans part number and you can find it at half the price of getting it from Audi. They come sealed and with the Oil pre-filled so just need to hook it up, vacuum it, and then Freon fill.
Thanks for the advice. I am located in Romania, eastern Europe. I looked up on ebay.de too with my mechanic to check the alternative if the engine is not rebuildable. We’ll see in a few days what the issue is and evaluate the costs. Wish me luck 
4.0tt swap!
Good luck on the engine. At least Romania isn’t too far from Germany compared to us in N. America. RS5 has a good point about a 4.0t swap if you’ve got the right people around and/or can do it yourself. We have access to a lot more 4.0t engines around here than 4.2 CFSA motors. If I had to swap again that is the route I will take. I’m sure in Europe you’ve got a lot of 4.0t motors around too, a fairly in depth swap though and it would be a bit time consuming but with the Torque they produce, it would be an absolute Monster. There are a few of them running around in B8/B8.5 platforms here in the U.S., some with the DSG, some with the ZF 8spd, not sure if anyone has done the 6spd manual although I’ve heard a lot of talk about doing one. Once again, good luck and keep us posted on the tear down of your engine, my heart goes out to you as I paid good money for a 26k mile supposedly good motor and had it fail at 300mi. No way to get that money back.
The motors are actually put together in Hungary interestingly enough!
Hello,
Just to follow up. I have the car back, with the full engine rebuilt, and so far all good, I changed the oil after about 600kms. They didn’t find anything obviously broken, the crankshaft was ok. There were some parts worn in the distribution and some other that were a bit loose. We changed all worn parts, springs, etc. The costs were about 12k euro (about 8k parts and 4k labor). The costs include also the change of oil for the transmission and differential. It took a lot of time, about 6 months and at least 2 months waiting for parts to arrive.
I also installed an X-pipe and wanted to de-cat it but it turns out the cats were empty anyway, so I left them.
Glad it did not require a swap or full rebuild. Was it the timing parts right (passenger) side?
