My x reg TD4 is having performance problems. The turbo doesn't seem to kick in until well above 3000 revs. Any idea what revs it should be kicking in at? Last week I was having to drop down to 2nd gear on a slight incline on the motorway because there was such a loss of power. Thanks in advance for any answers.

The turbo fitted to your vehicle has very little lag. This is achieved by the turbo effectively changing size. Confused? It's easy, at low revs its a little turbo that spins up easily, but then as the revs increase inside the turbo, the vanes are pushed out, thus making a bigger turbo with bigger boost. To remedy your problems, I would start with the hoses and clips, checking carefully for cuts and tears, you never know your luck!

Thanks for the reply. I've actually started by disconnecting the wiring to the mass airflow sensor and this seems to have done the trick. Next question is, can I leave this disconnected whilst I get a new sensor. I understand this means the sensor will work at default settings, but what does that mean for performance?

Glad to hear that it's on the mend. Not having had much involvement in the Td4, (its just a little after my time on the tools) I would'nt be able to direct you in the way of common faults, i.e; Chafed wire points etc. What I can say is that "Test-Book" will most likely be needed at some point! Some one will have more than likely produced a comparable piece of test equipment, for use at non-franchised garages. Sorry I can't help any more than that, had I known everything, I'd have called myself the Oracle!