I recently replaced my boost solenoids, and on a whim took one of my old ones apart like the guy in this video.
I'm having a hard time figuring out what exactly goes bad in them. It looks like it's just a coil with a rod in the middle attached to a diaphragm. The cap that goes over the diaphragm has to nipples, one for the vacuum source and one for the wastegate actuator. There is a vent on the other side of the diaphragm that exits from the big boxy knob sticking out the top of the solenoid. So what goes bad? Does heat damage the electrical connection? Warp the diaphragm? Does crud get in the connectors? I just don't see what there really is to fail because it's such a simple device. You all are smarter than me. A little help?
Btw, our solenoids look identical to the Volvo solenoid the guy in the video was taking apart.