A complete coolant regulation assembly that integrates the thermostat, housing, and outlet flange. Controls engine temperature by opening at 83°C to allow coolant flow to the radiator, preventing overheating. Ensures fast engine warm-up and consistent heater output for VAG 1.4 TSI EA111 engines.

The Thermostat, Housing & Coolant Flange Assembly (OEM: 03C121111AK / 03C 121 111 AK) is a premium-quality, integrated coolant control unit designed specifically for Volkswagen Group vehicles with EA111 1.4 TSI / 1.6 MPI / 1.4 MPI petrol engines. This complete assembly combines the thermostat, housing, and coolant outlet flange into one ready-to-install unit.

The integrated wax-type thermostat is calibrated to begin opening at 83°C, reaching full open at approximately 95–100°C. This ensures rapid engine warm-up when cold and proper cooling when at operating temperature.

• OE Quality: Manufactured to strict VAG OEM dimensional and material standards
• Integrated Design: Complete all-in-one unit combining thermostat, housing, and coolant outlet flange
• Precision Wax Element: Consistent, repeatable opening characteristics with corrosion resistance
• 83°C Opening Temperature: Factory-spec calibration for optimal engine performance
• Critical Engine Protector: Prevents overheating and astrophic engine damage
• Crack-Resistant Housing: High-quality engineered plastic resistant to warping and corrosion
• Restores Fuel Economy: Correct warm-up performance saves up to 15% in fuel consumption
• Ensures Cab Heating: Restores full heat output for driver comfort and safety

• Material Verifiion: Housing material tested to meet VW specifiions
• Dimensional Accuracy: Verified against OE blueprints using CMM equipment
• Temperature Calibration: 100% sample-tested to open at 83°C ±2°C
• Leak Testing: Each unit 100% pressure-tested for zero leakage
• Thermal Cycle Endurance: Sample units tested through 50,000+ cycles
• IATF 16949 / ISO 9001:2015 Certified: International automotive quality standards

• Individual Packaging: Moisture-barrier VCI bag with OE-style labeling
• Gasket/Seal: O-ring (03C121119F) sold separately
• Hardware: Mounting bolts not included (reuse originals if in good condition)
• Bulk Orders: Available in case packs (10, 20, 50 units)
• Customization: Private-label packaging for volume orders
• Fast Shipping: Worldwide dispatch via express courier or sea freight