Wow, so what have the dealer actually said now?
Funny you should ask. Literally just got a reply from the owner of the
dealership. Clearly, he's just hoping it's all going to just go away. On the plus side he's still offering to buy the car back.
Problem with that is finding a replacement. He's also saying that they will still take care of the car after the warranty runs out if something major happens.
However, he's basically not interested in investigating the noise beyond plugging in the diagnostic box. Will not start pulling the intake apart 'on a whim'. Says that as far as he is concerned the car is running fine and performing within specification so no action is required.
I find that a bit pathetic. If no action was required, why did they change the timing belt and the turbo? The noise which prompted those actions is unchanged so how come it mattered before and doesn't matter now?
The answer to that question is that so far, they haven't actually spent any money on the car! Both the timing belt and the turbo were replaced under my warranty so didn't cost him a dime. If he gets a tech in to look at it he'll have to pay for it so doesn't want to do it.
I'm not happy with his proposed options. We bought the car under the assumption that the noise had been diagnosed and would be fixed. We've now got a car with the noise not fixed and he's not interested in fixing it. The assurances of support don't cut it because how can I sell the car with a clear conscience? How could I sell the car to someone else knowing there is an diagnosed engine noise? I guess some people would be I wouldn't.
So quietly going away isn't going to happen. He has a rather long reply coming his way...