nikkomoon

I have a 2008 Audi A6 C6 with 186xxx miles, recently a full valve job, new headgaskets, and upper tensioners were replaced with audi parts. There is a loud ticking/knocking noise coming from the motor and I have no idea where it is coming from. I couldnt get it to throw a code until now and ive got a random multiple misfire code and misfire on cyl 1 and cyl 3. The timing/HG/Valves were done almost 2k miles ago. I have so far checked vacuum lines, checked vacuum, pulled the valve covers, no stuck rockers arms. Pulled the plugs, they looked fine but replaced them anyways, resistance tested coil packs, pulled timing covers, pulled oil pan to check pickup, pulled packs one by one to check for a rod knock as well as used the extension test to apply pressure on the piston to feel movement (if it was a rod bearing). I have also pulled the intake to check runner flaps, checked PCV, inspected for leaks in hoses there. No dice. I cannot find the issue with this engine, and I am 99% sure it is not a mechanical knock. I am also almost certain it is not the bottom end timing because a) it is in time, b) it does not make the sound turning over ONLY when running. Please Help i am going insane with this motor. I have 3 of these 3.2l FSI engines, and I have done this job on all of them. This is not my first rodeo with this motor and the others run like a top, 15,000 miles later. I am lost dazed and confused someone help me out.

nikkomoon

I should add, the noise started cruising down the interstate with cruise control on at 70MPH.

A6 4.2 Vier

It might help if you can pin-point the source of the knock with a stethoscope.
Also if you can post a video with sound.
Could it be something simpler like a variable timing solenoid valve?

nikkomoon

I don’t think they would go out and not throw a code, I’m pretty sure the vvs would throw a code. I attached a video below; sounds like it’s coming from driver side but I cannot pinpoint it with my scope.

nikkomoon

Heres the video

nikkomoon

video

nikkomoon

VIDEO

nikkomoon

let me know if the last one in all caps works, it should download it to your device

A6 4.2 Vier

No, I get a 440 login timeout message.

Sallad

no beuno