Turbo / Manifold squeal

[Bidja]

After asking around, I was told by a few mates that they are almost certain it will be the exhaust manifold warping, so that was the next step. Took it to some people that machined it considering it was quite warped, new gaskets and also repaired a pipe around the back (EGR I think) that had a small crack.

I got the car back and didn't hear the squeal for a bit but started to hear a whirring noise, especially at higher speeds like ~100kmph. That has become more consistent at most speeds now, usually being very clear around 2600rpm - 3000rpm.
Cheers
Oli

Not sure how you will go for a further warranty claim_can only try.

IMO, if the exhaust manifold was badly warped, suggest a new replacement manifold be fitted and use inconel studs_if stock were reused at time of manifold install they most likely would have continued to stretch and elongated now to point of failure_ the first two studs are a common failure:

https://www.tillix.com.au/product/in...ud-singly-buy/

Would make sure that the EGR pipe was repaired and replaced successfully.

With manifold and dump pipe removed, suggest you block the EGR assy off with a blanking plate at both the exhaust manifold and at inlet manifold ends. Can do a resistor mod at back of MAF sensor plug wiring loom (in series with pink wire), if the EGR has not been turned off with ECU remap. These mods will prevent the 401 fault error code illuminating MIL.
The EGR pipe replace without blocking off will split again in time (maybe 150,000kms).

Have a read:
https://www.patrol4x4.com/threads/cr.../#post-6890645

Do these 2 things first, especially if no excessive sideways movement is felt of turbo turbine shaft (causing the comp wheel rubbing against housing bore). Test by applying sideways back/fwd finger pressure to inlet end of turbine shaft.