I looking to replace my Vacuum Control Valve (otherwise known as the "proportioning valve" I believe in the Brotherton article) due to the fact that is leaks slowly from the top port, but I'm not sure exactly how to test a new(or used rather) one to see if it works. I understand that they are supposed to control the amount of leaking in the vac system, but I don't know the proper testing procedure to see if one is good or not. I do have a mityvac but not sure how to test it due to the attached lever that controls the leak.

If anyone can please shine some light on this subject I would greatly appreciate it. I'm trying to smooth out my transmission shifting and have hunted down my last leak (after fixing about 10 other ones all throughout the system) at the VCV.

Thanks,
Dan