I seem to be having an actuator problem. I checked the vacuum lines going into the two wheel drive side of the actuator. I am geting 12inhg of vacuum preasure on the guage while idle. This seems to be a bit low or I might be wrong. I check back both sides of the 2wd selionid and got 12inhg there also. There is nothing coming out of the 4wd side when in 2wd as it should be. No light for 4wd on the dash when in 4wd and one of the tires drags in 4wd. When in 2wd it sometimes acts like its in 4L. Whats the best way to check to se if the actuator is working properly.