CM870 VGT Actuator

[Chamberpains]

What were the codes for the actuator? There are no direct codes for the actuator itself failing because it is 100% pneumatic with 0 direct electrical feed back.

A very common problem of the actuator control module failing will throw a lot of things out of whack. This module does throw codes when they fail completely. It's an expensive little thing but they do fail by commanding the wrong amount of pressure to the actuator. Do not go to ebay for a cheaper reman 1 if you decide to replace it, they are junk and piss poor remans. 100% new holset unit is the only way to go and even they can be wrong right out of the box but they are by far better than the half-assed reman crap they're pushing elsewhere. Call around to dealerships or wherever for the beat deal. Usually range $800-$1000

Also be sure there are no leaks in the plumbing to the actuator. The smallest pinch, kink or leak will result in off boost levels.

If you haven't checked yet, check your CAC circuit for new leaks.