2.7 Diesel Engine whine - turbo issue?

[PaulGover]

My 2008 2.7 TDVi has developed a quiet whine that seems to be partly related to engine speed and throttle opening - i.e. accelerating makes the noise rise in pitch, taking your foot of the gas drops the pitch faster than the car's speed decreases. I'm wondering if it's either a turbo, perhaps its bearings failing, or perhaps one of the cooling system pumps (IIUC there's a separate one pumping hot water around the air-con).

I've hardly ever read about Jaguar turbos failing; there are a couple of items in the S-type forum and that's about it. Anyone got any experience to pass on? I guess it would be worth getting the car on a ramp and checking listening with a stethoscope, if the turbos are reachable.

[rosemary]

Lets hope it's not the Turbo have you had "Restricted Performance" alarm up?. Has the Cam Belt been changed and was the Water Pump and Idler Pulley replaced at the same time. Run some Turbo Cleaner through it for a couple of tanks full of Diesel before doing anything with the Turbo. Both my diesel cars, S-Type at 151,540 mls and XF at 100,000 mls had faint whines from the Idler just before both the cam Belt changes at 95,000 mls.
Dave

[PaulGover]

Thanks Dave. Had the cam belt changed at a full dealer service, and AFAIR they also did the idler; not sure about the water pump. No Restricted Performance or other messages. Runs fine at the moment.
I'll try the cleaner; is that something from Halfords or similar?

[rosemary]

Yes Halfords has all sorts. I used the Turbo Cleaner in my S-Type 2.7 a couple of times after getting restricted performance alarm when first starting the engine after a cold night. Seems to have done the trick.
Dave