Calibration

Calibrate sensors before you chase fueling. Wrong TPS closed, wrong MAP transfer or a CLT on the GM curve when you fitted a Nissan NTC will waste a day.

1. 015 V rails

   Key-on, engine off. 5 V Sens 1 and 2 should be 4.95–5.05 V. If a rail is at 0 V, something is shorted — unplug sensors one at a time.

2. 02MAP

   Key-on, engine off. MAP should read local baro (≈ 90–102 kPa depending on altitude). A 3 bar sensor reading 200 kPa at key-on has the wrong transfer or a 5 V problem.

3. 03TPS

   Calibrate closed and WOT. Confirm 0–100 % sweep.

4. 04CLT / IAT

   Stone-cold engine: both near ambient. Hot soak: CLT at thermostat.

5. 05Battery

   Confirm the ECU battery voltage matches a meter at B18. Injector dead-time is voltage-based; a 1 V error is a lot of fuel at idle.

6. 06AFR

   Key-on, sensor at air: wideband should read free air (λ ≈ 1.5+ / AFR 20+ depending on controller). A stuck 14.7 is a narrowband or a dead analog scale.