I recently added a boost gauge and found that my new (used) evo9 was not boosting more than 10psi. I did a boost leak check and the car held 26 psi before the DV started to leak.

I then pulled the vac line off the wastegate actuator and was able to boost well above 20psi (controlled test).

I double checked my vac line routing from the BCS to the turbo outlet and actuator. I ensured the pills were installed correctly. I suspect the soliniod has failed.

Is there a way to test the BCS via volt meter with the car at idle?

 

You can probably check the resistance with an ohmeter, I don't think voltage will tell you anything. I'd check mine, but I don't have my Flukes wth me.