Blow off Valve Diverter for Audi A4 (2005-2019) 2.0L

Direct-Fit Blow-Off Diverter Valve Upgrade for 2005-2019 Audi A4

What it Does: The Blow off Valve Diverter for Audi A4 replaces the leak-prone factory diverter assembly on 2005-2019 models to maintain peak boost pressure and accelerate turbo spool recovery between shifts.

The Stock Audi A4 Diaphragm and Solenoid Failure

Factory diverter valves across the B7, B8, and B9 generations frequently suffer from mechanical degradation under elevated boost and thermal cycles. Original equipment rubber diaphragms are notorious for tearing, causing insidious boost leaks, erratic idle, and sluggish throttle response. Even later OEM revision piston valves suffer from spring fatigue and blow-by past the plastic housing under higher manifold pressures, bleeding charge air back into the intake tract before it reaches the combustion chamber.

The Engineering Solution

This upgraded diverter assembly solves pressure leakage using a CNC-machined, black anodized billet aluminum body fitted with a precision internal brass piston and matched return spring. Designed as a sandwich-style bolt-on that integrates directly between the factory solenoid coil and the compressor cover, it preserves electronic actuation while mechanically securing boost holding. High-temperature Viton O-rings ensure an airtight seal against the turbocharger housing, eliminating boost flutter and venting cleanly to the atmosphere for distinct acoustic feedback without triggering ECU torque intervention.

Technical Specifications

Compatibility

• 2005-2008 Audi A4 2.0T (B7 Platform, EA113 Engine)
• 2009-2016 Audi A4 2.0T (B8 / B8.5 Platform, EA888 Gen 2 Engine)
• 2017-2019 Audi A4 2.0T (B9 Platform, EA888 Gen 3 Engine)

Frequently Asked Questions

Does this fit the B8 and B9 A4?
Yes, this is a direct fit for the 2005-2019 Audi A4 equipped with the 2.0T EA888 and EA113 engines.

Will this blow-off valve trigger a Check Engine Light (CEL)?
No, because it utilizes the factory electronic solenoid base for operation, the factory ME7/MED17/Simos ECU retains full control over valve actuation without throwing fault codes.

The Audi Precision Standard

Engineered to meet the exact mechanical tolerances required by German forced-induction platforms, this billet diverter kit ensures zero charge-pipe pressure loss and completely seamless integration with the factory engine management system.