Advanced Diagnostics
Advanced Diagnostics - DTC P050B: Cold Start Ignition Timing Control System Performance ProblemGeneral 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) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type, OBD Status
Enable Conditions
Malfunction Threshold
The engine speed [ENGINE SPEED] is 2,200 rpm or more for at least 3.5 seconds.
Possible Cause
NOTE: The causes shown may not be a complete list of all potential problems, and it is possible that there may be other causes.
- Intake air duct breakage
- Intake air duct misinstalled
- Air cleaner breakage
- Air cleaner damage
- Air cleaner clogged
- Mass airflow (MAF) sensor failure
Confirmation Procedure
With the HDS
None.
With the Driving Pattern
1. Allow the engine to cool to an ambient engine coolant temperature [ECT SENSOR 1] of 140 °F (60 °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 engine coolant temperature and intake air temperature 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 engine coolant temperature and intake air temperature 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.