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.

• Hardcoat anodized aluminum valve combats premature wear
• A replacement ratcheting end plug is included, as the OE one often breaks
• An adjustment tool is provided in tool kit F-119940-TL5 for repeated assembly, disassembly and adjustment of the ratcheting end plug