Question about fluctuation water pressure

[slash007]

When you installed the rebuild kit, which kit did you use? the rubber parts kit or the complete kit that includes everything inside the backflow unit.

I bought the total rebuild kit, replaced every part. To be fair, it did fix my problem of water running all the time. I wonder what is causing the fluctuation in pressure and want to be sure that the backflow is the issue. I do have others installed at other locations and everything is bone dry.