litton wrote:
If so, what controls the vane position? Also, is there any chance that the vanes are sensitive to cruding up from the crankcase blowdown that is introduced to the inlet?
Vanes are vacuum controlled on our model (the ganglia of tubing & stuff just behind the air filter box).
Yes, in general VGT's are sensitive to cruding up (coking) from passing excess unburned residual motor oil mixed with soot (ie..keep the motor oil out of your CAC). When this happens, the vanes will "stick" and the turbo won't spool properly but I have yet to see anyone with a CRD report a failure from this problem. This style of turbo is also known to loose vanes if struck by a chunk of carbon (caused by a build-up of soot & unburned oil, then breaking loose and getting sucked into the vanes).