1. Identify the exact sensor
Record the part number, connector and manufacturer transfer data. A housing marked with a pressure range is not enough to define a voltage calibration. Check the supply, signal and return pin assignments using the actual data sheet; similar-looking three-pin sensors can have different assignments or curves.
2. Separate absolute and gauge pressure
Confirm the reference before comparing a MAP value with a boost target. Gauge pressure is absolute pressure minus local ambient pressure. As an arithmetic example, 200 kPa absolute at 100 kPa ambient equals 100 kPa gauge. That example is not a fixed atmospheric correction for every altitude or weather condition.
3. Compare a static reading
With the engine stopped and the pressure port exposed to the appropriate ambient reference, compare the ECU reading with a suitable reference measurement. Record raw voltage if available. A mismatch can involve calibration, supply, pinout or the pressure path; changing the display from kPa to bar does not correct the transfer curve.
4. Inspect the pressure path
Identify where pressure is taken and inspect hose routing, restrictions, leakage and mechanical security. Do not infer actual manifold pressure from a sensor installed on an unsuitable reference point. If readings respond slowly or disagree under changing conditions, compare the installation and logging times before concluding that the ECU calculation is wrong.
5. Validate before relying on protection
Keep the sensor calibration, reference measurements and installer observations in the project record. Ask the tuner to validate the range needed for the intended operation before setting boost-related limits. A plausible idle number alone does not prove that the curve, range and pressure path remain correct across the working envelope.
Official references
Editorial summaries; use the matching manufacturer manual for actual wiring and calibration.