Car: VW Touareg
2007 2.5 TDI
Does not engage the clutch plates when cold and slips in all gears. When you take your foot off the accelerator, the revs drop down to idle while still travelling at speed. The quickest way to fix this, while driving, seams to be getting up to 6th gear and then manually dropping the gear and letting the car engine rev up and brake it self letting the revs get down close idle and then keep dropping and repeating through all gears down until crawling in 2nd.
Even after it is warmed up. When you are accelerating (mostly in 1st, 2nd and 3rd gears) the engine pulls ok. When you get to higher revs, without changing gear, the revs then drop a bit as the clutch then finally engages properly with a small tug.
My opinion: When the clutches engage it pulls fine, but it feels like that the mechanism/solenoid that fully engages the clutch plates is a bit slow/sticky?
I took it to an automatic transmission centre who checked the fluid levels which were good and clean red colour. He also drove it and saw no real problem, as the engine was warm.
Any ideas as to why this happening and what could possibly be the cause?