In Saturn TAAT units, poor line rise results when excessive wear occurs in the boost sleeve assembly. This prevents the pressure regulator valve from being stoked to the high line position. Valve wear can also result in the boost valve sticking, causing unintended line rise. Sonnax boost valve kit 95200-03K restores line pressure.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.