If you find an air leak around you breathers let me know, I have checked my rubber and replaced it all, I actually have a new pair of breather hoses. Changing the rubber has helped my idle but, I still have the wierd idle at park.In response to Kebowers, The only leak I have not checked for is the injectors I will try checking those at the next opportunity thanks.
2005 320 CDI
2006.5 VW Jetta TDI
1991 560SEL (179000 Sold)
1972 280SEL 4.5 ('The Lead Sled' 320000 miles when sold.)
1972 220D (225000 when sold)