MAF calibration

Mass-air-flow sensor characteristics and a ready 64-point curve for MS3: pick the sensor, enter your housing diameter, get the volts-to-g/s table for the MAF Flow Curve in TunerStudio.

Sensor

Flow-bench validatedAudi RS4 B5 2.7T · Audi S4 4.2

The polynomial was taken for the measuring insert of this diameter. If the insert sits in a housing of another size, enter the actual inner diameter below.

Housing

Multiplier
×1.000
Curve ceiling
1820 kg/h · 506 g/s

First-order model: the element measures speed in its own bypass channel, and at the same mass flow that speed falls inversely with cross-section area. At the ends of the range the velocity profile in a wider tube differs, so expect a few percent.

Curve

0.045591013651820012345V

Your measurements

MAF voltage / flow pairs from a log or a scan tool. "Fit housing" stretches the factory curve onto them; "Build curve from points" derives a curve from scratch — that is the path for a sensor with no calibration. Spread the points wide in flow: between them the curve is interpolated, above the top one it is extrapolated.

MS3 table, 64 points

Copy and paste into the MAF Flow Curve in TunerStudio (columns: volts, g/s). Set maf_range = 650 g/s before loading — it is the smallest range that fits the top of the curve and gives the best resolution down low.

#Vg/skg/h
10.0000.000.0
20.9800.000.0
31.0000.000.0
41.0660.853.1
51.1311.766.3
61.1972.739.8
71.2623.7513.5
81.3284.8417.4
91.3936.0021.6
101.4597.2226.0
111.5258.5230.7
121.5909.8935.6
131.65611.3540.9
141.72112.9146.5
151.78714.5652.4
161.85216.3258.8
171.91818.2065.5
181.98420.2172.7
192.04922.3480.4
202.11524.6288.6
212.18027.0597.4
222.24629.65106.7
232.31132.42116.7
242.37735.37127.3
252.44338.52138.7
262.50841.87150.7
272.57445.44163.6
282.63949.23177.2
292.70553.27191.8
302.77057.56207.2
312.83662.12223.6
322.90266.96241.0
332.96772.09259.5
343.03377.52279.1
353.09883.28299.8
363.16489.38321.8
373.23095.84345.0
383.295102.67369.6
393.361109.89395.6
403.426117.52423.1
413.492125.58452.1
423.557134.10482.8
433.623143.09515.1
443.689152.59549.3
453.754162.61585.4
463.820173.20623.5
473.885184.36663.7
483.951196.15706.1
494.016208.59750.9
504.082221.72798.2
514.148235.58848.1
524.213250.21900.8
534.279265.66956.4
544.344281.971015.1
554.410299.201077.1
564.475317.391142.6
574.541336.611211.8
584.607356.911284.9
594.672378.371362.1
604.738401.061443.8
614.803425.041530.1
624.869450.401621.4
634.934477.221718.0
645.000505.591820.1