the roadie said:
Erratic idle is one clue, if the other cures for erratic idle don't work. Or a SES light accompanied by a code that says the CPAS is the culprit.
I ran across this thread while researching the P0014 code on my wife's 2004 Trailblazer.
She has been getting P0014 from time to time. It comes on and then goes out by itself. It was on today when I checked it. I cleared it and then sat down at my computer. She also has been getting erratic cruise control actuation. No erratic idle or other engine performance problems.
I pulled the camshaft position actuator solenoid and found the middle screen clogged just like the above photo.
I cleaned it with brake cleaner and low pressure air. Put it back in and took it for a 10 mile test drive.
No more check engine light. I turned on the cruise control about 60 times and it never missed a lick.
I read that the sensor on the front of the engine (don't remember exact name but it is another part of the camshaft system) will affect the cruise control.
Maybe the problem is there but for now it's working.
Thanks to everyone who posted and especially for the detailed photos.