Bought this yesterday, no problems on test drive, pulled hard in all the gears. On the way home from dropping of seller, warmed up and under hard acceleration, this screeching noise can be heard from the engine bay.
Noise is loud, happens under hard acceleration at first and then normal acceleration, until you keeps the revs low for a while, then it will accelerate normally again without the noise.
There is a dip in power when making the noise. Without the noise it picks up speed very good.
No black smoke.
Any ideas? I'm worried i've bought a dud. I'm hoping it's a pulley, but power is affected so maybe it's the turbo?