Standard Ignition MAS0239 Mass Air Flow Sensor

Mass Air Flow Sensor for Audi A4 and A6

Standard Ignition MAS0239 is a complete mass air flow sensor assembly built for direct replacement on select Audi applications. It uses a bolt-on mounting style with a molded PVC housing, a rectangular female connector, and a 3-blade male terminal layout for a straightforward OE-style connection.

Key Features

• Complete assembly with housing included
• Bolt-on attachment method with 4 bolt holes
• Rectangular female connector, 1 connector
• 3 male blade terminals
• Molded PVC construction
• Direct-fit replacement for select Audi A4, A4 Quattro, A6, A6 Quattro, and S4 applications

Detailed Description

Standard Ignition MAS0239 is an emission control sensor used to measure incoming air volume for engine management on compatible Audi vehicles. Accurate airflow input supports proper fuel delivery, idle quality, and drivability. This part cross-references Hitachi Automotive MAF0021 and NGK 59062 for the same application. Fits 1998-2002 Audi A4, N/A; fits 1998-2002 Audi A4 Quattro, N/A; fits 1998-2001 Audi A6, N/A; fits 1999-2001 Audi A6 Quattro, N/A; fits 2001 Audi S4, N/A.

What It Helps Address

• Rough idle caused by inaccurate airflow readings
• Hesitation during acceleration
• Lean or rich fuel trim conditions
• Check engine light related to air metering faults
• Poor throttle response and drivability concerns

Installation Notes and Tips

Verify connector shape, terminal count, and bolt pattern before installation. Inspect the intake tract, air filter housing, and wiring connector for contamination or damage that could affect sensor performance. Because this is a complete assembly, compare the existing unit to confirm the housing and mounting style match the vehicle.

Quality Assurance

Standard Ignition manufactures replacement emission control components for service applications, and MAS0239 is built to match the listed fitment and connection style for the specified Audi models.