Low spring rates, incorrect spring heights and inappropriate replacements from previous rebuilds can lead to low base line pressure. The Sonnax replacement spring 77917-08 provides a resultant idle base line pressure of 72 psi, and 82-85 psi cracking pressure, which is consistent with the OE orange spring
Low line pressure resulting from worn boost valves, a worn pump bore at the pressure regulator valve or pump pocket wear will not be corrected by this spring.
Sonnax valve body layouts provide a detailed overview of individual units making it quick and easy to determine what’s available for the specific valve body you’re working on. See all Sonnax valve body layouts.