Re: 156 engine rattle.
Hi - Have you had a diagnosis yet?
I have a 156 2.0 TS with 78K on the clock - belts OK and recent oil change. I had a similar experience - pulled on to motorway M27 near end, and noted a tinkling at about 4000 rpm in 3rd - I eased back and settled at about 2500 - 2700 in top where it was almost inaudible. - no warning lights or loss in power. I suspected the variator as I had been told they can rattle but should not affect performance.
I continued gently on to the A31 for a couple of miles but noted the sound got a bit louder under load uphill. I pulled over as soon as possible but it had developed into a rattle. It was still running smoothly but b..... noisy - turn off quick! - AA home - Local Alfa garage listened and suspect bottom end (as was my thought), but said they had never seen a failure of big end caps or bolts. The difference is shells at about £200 or replace engine £1500 - £4500.