Wear at the inboard end of the boost regulator bore in VW/Audi 01M, 01N and 01P units can reduce the ability of EPC/TV pressure to stroke this valve open. Full boost exiting this valve combines forces with the main regulator spring, increasing line pressure. Sonnax oversized boost regulator valve kit 119940-05K allows the valve bores to be refurbished.
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.
Vacuum testing at the port(s) indicated fails to hold the recommended minimum in-Hg, or if wear is visually detected.