Problems with the revs

[Tomcat]

I seem to have an ongoing problem with the new car, if I drive it hard(i.e. upto 5k rpm) then change gear the revs dont seem to drop fast enough. There seems to be a bit of 'lag' between taking my foot of the accelerator and the revs dropping. This is a problem when trying to drive quickly up through the gearbox, i've changed the accelerator cable(which was stiff) and I've had the throtle body off and cleaned it up. Checking the return of the throttle with the engine off, there doesn't seem to be a problem, could this be down to air being drawn in somewhere?, I have no warning lights on by the way.

[JackT5]

When i first got mine i was worried there was something wrong but was told by several people that it was the way 850 T5's were set up, particularly ex police. Theres a divided view on it, some say a dose of carb cleaner cures it, although on mine it didnt so i learned to live with it. I never found a problem going up the box but often double de clutched comeing down to give the revs time to drop.

[BlackBeast]

I think racer found the problem to this. There is a pipe that goes from the inlet manifold to the intake pipe that has 2 white non return valves in it. You should be able to see it by looking down at the turbo as it connect very close to the pcv valve.

[Tomcat]

And what's wrong with this?, is it the none return valves that stick or is it a split pipe??.