Thought i would start a new thread on this specific subject rather than hijack the "S-type called a Mondeo" post.

My 2005 STR makes exactly the same noise, and I notice that little or no air is coming out of the centre vent even when the car is heating up after a cold start. I have had a look at JTB00066, but my VIN does NOT fall within the range N53000 to N91220 (years 2006-2007). Coolant level is OK, by the way.

Sounds like a pricey repair job to replace the servo motors and maybe the DCCV. Would really appreciate any opinions and advice.

 

I've never been clear why it was a restricted VIN range unless they changed vendors for the motors or some such. It may be the best range they could estimate - but perhaps wrong?

Ticking / buzzing could easily be a stepper motor (*) but bubbling? I reckon not. That would have to be something liquid and there's none of that in a stepper.

(*) such as "hunting"

I don't see how the DCCV could be the cause of the noise as it's a long way away and its failings are rather well known. But it could be the cause of inadequate heat (the valve(s) stick, more often open but sometimes closed or in between).

I'd live with the noise as yes it sounds painful and expensive to fix. But I'd replace the DCCV if you can DIY.