Advanced Diagnostics

DTC P050B (167) Advanced Diagnostics

DTC P050B:

Cold Start Ignition Timing Control System Performance Problem










General Description

The quick warm-up system supplies additional air and retards the ignition timing when the engine is cold to activate the catalytic converter as quickly as possible. When the actual engine speed is a specified fast idle value, and it continues for a specified time, the powertrain control module (PCM) a malfunction and stores a DTC.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status





Enable Conditions





Malfunction Threshold

The engine speed is 2,000 rpm or more for at least 3.5 seconds.

Driving Pattern

1. Allow the engine to cool to an engine coolant temperature (ECT) of 131 °F (55 °C) or less.
2. Start the engine, and let it idle for at least 10 seconds.

Diagnosis Details

Conditions for setting the DTC

When a malfunction is detected during the first drive cycle with the ECT and intake air temperature (IAT) at engine start-up within the specified temperature range, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle with the ECT and IAT at engine start-up within the specified temperature range, the MIL comes on and a Confirmed DTC and the freeze data are stored.

Conditions for clearing the DTC

The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.