Help troubleshooting Idle Quality issues

EDIT: Was my fuel pump... In tank.


Maybe it's nothing but I thought I'd ask the experts here. 2004 Jetta TDI wagon.

I noticed in the last couple weeks my car sounds different at idle. It almost sounds like a carburated car that's running rich and has a slight stumble/miss.

(anyone here old enough to remember carburated cars? )

So it has a slight miss is the best way I can describe it. Thinking it was fuel related because we're in the middle of switching from winter diesel to summer diesel, I added some power service supplement and it did seem to make things a bit smoother but the miss is still there.

Another thing I noticed is I think my fuel pump is louder when it primes I used to never notice it but now it makes a fairly noticeable thumping when I turn the key.

Car runs fine apart from that mileage seems normal.

Anything I can check in VCDS? Cam issues? Injector issues?

Injectors pooched? They used to all be 0.06 or around there when I did my last timing belt. Car still runs fine but is idling worse and worse as the weeks go by. Anyone have a how too on changing them and do I need special tools(and heck can I still get parts)

Check the cam lobes.

Pull the valve cover and feel for sharp edges on the cam lobes.