Circuit Description

Engine load is determined using a "speed density" method. This method is calculated using inputs from Manifold Absolute Pressure (MAP) sensor, Crankshaft Position (CKP) sensor, Intake Air Temperature (IAT) sensor and engine RPM. The MAP sensor is the main sensor used to calculate engine load. Powertrain Control Module (PCM) supplies a 5-volt reference signal and a ground circuit to MAP sensor. As manifold pressure changes, MAP sensor input voltage to PCM varies from less than 2 volts at idle to greater than 4 volts at Wide Open Throttle (WOT). If PCM detects MAP sensor input voltage that is excessively low, DTC P0106 will be set.

Conditions required to set DTC are:

• No ECT, CKP, EGR, EVAP, MAP or TP sensor DTCs present.
• ECT is greater than 14°F (-10°C).
• EGR flow rate is steady, changing less than 2 percent.
• Engine speed is steady 1000-4000 RPM, and changing less than 20 RPM.
• IAC valve counts are steady, changing less than 3 counts.
• TP sensor position does not vary more than 5 percent.
• No status change in brake switch, A/C clutch or power steering pressure switch.
• MAP value varies more than 10 kPa, for a total of 10 seconds within a 20-second time sample.