My 08 jetta's engine randomly started to become really loud,you cant hear it when its idling.But you can hear the difference once the car is going around 30-40 mph. any ideas?
i have a video of the noise:
i dont know if its possible to tell the difference in the video but i hope it helps.
the car sounds normal until 0:12 then you can hear the loud noise.
at 1:08-1:30 you can hear how loud it gets.

 

Welcome to the forum Alex.

Its a pity we don't know more details about your motor.

https://volkswagenforum.com/forum/ne...gnature-34185/

If its a TDI then it sounds like you could have a camshaft and lifters on the way out.

VW and Audi TDI camshaft wear: camshaft, lifter, and bearing inspection and replacement - PD engine