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 ignition timing is not retarded, 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
| Execution | Once per driving cycle |
| Sequence | None |
| Duration | 9.9 seconds or more |
| DTC Type | Two drive cycles, MIL on |
| OBD Status | PASSED/FAILED/EXECUTING/OUT OF (TEST) CONDITION |
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Elapsed time after monitor finishing condition | 2.5 seconds | - |
| Battery module capacity | 0 % | - |
| Engine coolant temperature [ECT SENSOR 1] |
14 °F (-10 °C) | 176 °F (80 °C) |
| Throttle position | Fully closed | |
| Other | Vehicle stopped | |
[ ]: HDS Parameter
Malfunction Threshold
The ignition timing deviation is 10 ° or more for at least 9.9 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
- Engine coolant temperature (ECT) sensor 1 failure
- Engine coolant temperature (ECT) sensor 2 failure
- Ignition system failure
Confirmation Procedure
Operating Condition
- 1.
Allow the engine to cool to an ambient engine coolant temperature [ECT SENSOR 1] of 140 °F (60 °C)* 1 (122 °F (50 °C))* 2 or less.
- 2.
Enter the maintenance mode, then start the engine, and let it idle for at least 10 seconds.
*1:: '14-15
*2:: '17
With the HDS
None.
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 12 volt battery.