2012 Pathfinder 4.0 P0021

Bank 2 intake cam angle doesn't match request.  I controlled the solenoid on both banks with the scan tool and thought bank 2 was responding slower and not as much as bank 1, and made a bad call by putting in a solenoid.  After installing I see that b2 will only advance to 5* with my command where bank to will reach 9*.  I see that the ECM is sending the command to the solenoid with the scope, but it's only able to reach that 5*.  I'm thinking it is either an oil pressure problem on that bank, or the actuator on the cam isn't fully moving.  

In general, how can you determine if it's the sprocket or the solenoid that isn't working properly?  I've energized a million solenoids on the bench and they nearly always move in that scenario, but I've seen them not working during the active test on the vehicle.  Maybe there is a seal on b2 that is bleeding off pressure?  At this point I'm confident that the cover has to come off to fix this, but I would like to know how to avoid making this wrong call again in the future!

I check, and compare, the range of all actuators by manually activating the solenoids, at idle, to 100%, and measuring the offset of each cam sensor with the crank. You can, also, measure solenoid voltage and current, just like an injector.

So B2 will only move 5*, and no more? While B1 will go full range?

I like to see a pintle hump on a current ramp, with the solenoid installed in the vehicle. If I see a hump, and the timing didn't change (or change enough), it gets an actuator/phaser/sprocket.