G60 rod bearing noise?

[BarberG60 10]

My G60 turbo converted Jetta is making a faint but noticeable noise.

 

You can hear it when driving or when idle at around 2/2.5k revs. It's only there on light throttle, doesn't appear to do it on full throttle.

It sounds like a light knocking noise. It's not loud, but is there

 

Initially I was convinced it's coming from the gearbox, as that's the side of the engine bay it appears to come from, but am now thinking it could be the rod bearings.

 

No drop in engine performance or any other signs .At idle the engine sounds very healthy and ticks over smoothly.

 

Anything else that would indicate rod bearing problems?

 

Are they a simple fix?

 

Thanks

[Jim 1]

If it is the bearing shells, I guess the question is what is the underlying reason why they have become worn? I've never done them myself, but I understand it's a relatively easy job to replace them - just need to drop the sump to get access to them.

[Dox 22]

You can replace the big ends by removing the sump, you can check the mains in the same way but replacement requires dropping the crank so engine or gearbox removal. Little ends require sump and head off to check / replace.

 

An oil pressure check would be the place to start or maybe a change of viscosity to see if it worsens or improves?

 

Is there a restrictor to the turbo oil feed? Something else you could play with, larger or smaller, but I wouldn't do this without fitting an accurate oil gauge first.