Re: help!!!! having wastegate problem
Same way you test any solenoid valve.
Off the top of my head, I'd apply pressure to the port on the BCS that receives boost/vacuum from the intercooler pipe. Apply and remove voltage and note changes in where the air is going (being bled off or going to the other nipple), note reaction time as well if you think yours is sticking.
Could be wrong, no time to look at an actual BCS right now.