Patient is a 2006 Range Rover 4.2 supercharged with 92xxx miles. She went on a 500 mile trek today, and on the way, no problems. Averaged 24.2mpg (hand calculated), loved every minute.

On the way back, I stopped to pay a toll and heard some tapping. I revved the engine, sure enough it was me. Power is still the same, but it is a steady rattling that seems to be emanating from the passenger side valvecover. I know the M62 has timing chain issues, and from what I see each head has a tensioner on the jag engine. Are these prone to failure? Oil is clean and full.

Could use some input here.

Thanks!

 

Another thing to consider is the supercharger coupler between the snout and the housing.
Crank her up and use a stethoscope to listen to the valve cover and help narrow down location. Use it on the snout of the supercharger as well.

You could then remove belt and check the lash on the supercharger pulley as well.

 

That is the gameplan. However, the ticking is very rhythmic, I am all but positive it is internal to the engine/valvetrain (passenger side).

I did just replace all the belts, and fitted a smaller supercharger pulley, so its not out of the question something isn't right there.