AKN Motor Noise: Clicking, Tapping, or Knocking

Hello,

'For the past few weeks, I've noticed an unusual noise in my Passat AKN.'
It started with a light, metallic rattling sound from a cylinder. This can be heard when the engine is decelerating while in drive.
In addition, there's a dull thumping sound coming from the air filter housing when the engine is idling. This dull sound has become particularly noticeable, and it seems to be synchronized with the firing of one of the cylinders.
In addition, the car only starts after a considerable amount of cranking in the morning, and the overall performance is lacking. However, it could also be a different issue, as the loss of power already existed before these noises started.

*EDIT: No error was found. However, in group 13, the maximum difference between cylinders 2 and 3 is 3.7 mg/stroke, while all other cylinders have differences between 0.3 and 1.6 mg/stroke.
mg/vial

I have a workshop appointment on Tuesday, but maybe someone here can offer some suggestions about where the problem might be. The car has 169,000 kilometers on the odometer.

Thank you in advance.
Regards,
Jean.

My condolences.

Okay, let's start saving up for new camshafts. I'd like to know what they're asking for.

Greetings.
Rainer.

Okay, so my AKN engine also needs new wave springs. However, I've heard that the hydraulic lifters can burst and the rocker arms can break. I can't explain the noises on my own without the wave springs. Also, I can't attribute it to the idle speed control, as all of mine are working correctly.

"I was tasked with testing all the fuel injectors at the workshop, and while I was there, I was also asked to inspect the connecting rods. The cylinder head covers will already be removed at that point. Then you'll definitely be able to pinpoint the problem."

Vielleicht hast du Glueck und ist es "nur" eine Duese. Good luck!

PS
What they want: approximately 1100 for materials and 1100 for labor without a timing belt, and about 500 more with a timing belt. I can't give you the exact figures right now, as I don't have my cost estimate in front of me. I'm doing it myself now, but it's a huge amount of work.