Weird idle noise.

[SampaGuy]

So my bro's car (my old jetta for those that remember) just started sounding like a diesel truck during idle. When I slowly give it throttle this noise will get louder and louder until about 1200rpm, then the noise stops and the engine sounds nice and smooth from then on. Once the RPMs are back under 1200 the rattling/chatter noise comes back. Car drives fine. Had this car for almost 3 years so I know its not normal.

He did drive the car with about 2 quarters of oil missing for a while because he is a moron. But that was a couple of months ago and this noise just started recently (and there's enough oil in there now).

I popped the hood and the sound comes from the timing belt side of the engine but its hard to distinguish if its coming from inside the engine or if its from the AC compressor or something else in that area.

Any ideas?

2001 VW 1.8t

[hadouken]

could it be the turbo?

[j0nbunklah0m]

maybe the timing belt is loose? mine is and it does similar noises

[Barefoot]

vid of sound