Right then, i have a caddy '02 1.9tdi ALH. I have had a few intermittant turbo problems, one minuite over boosting, the next it under boosting. Stripped the VNT and its nw mint and totally free and functioning perfectly. However i am getting too much vac to the actuator, hence it is sticking in the high boost permanantly. i have, Checked the correct routing of the vac pipes (all now new and checked again after) swapped the N75 with the EGR solenoid, no difference stripped turbo and is as free as anything Checked that the actuator holds vacuum, it does is it possible that the vacuum check valve could be the problem? i have got full registered version of VCDS at my disposal, so just need to know how to use it! Starting to wind me up now to be honest, and when i get wound up i can't think straight. Cheers guys.