DTC Advanced Diagnostics: P2187 (3.0L Engine)
DTC P2187: Fuel System Too Lean at Idle
General Description
If the evaporative emission (EVAP) canister purge nozzle is disconnected, the intake airflow increases and the air/fuel ratio becomes lean. The disconnection of the EVAP canister purge nozzle can be monitored by the values of the air/fuel ratio feedback, the air/fuel ratio (A/F) sensor (sensor 1), and the target air/fuel ratio. The value used for detecting malfunction is calculated by the following formula.
Long fuel trim + (plus) short fuel trim + (plus) (A/F sensor (sensor 1) value - (minus) target air/fuel ratio)
If the value calculated from the formula above is a specified value during the idle after the engine is warm enough, the powertrain control module (PCM) detects a malfunction and stores a DTC.
Monitor Execution, Sequence, Duration, DTC Type
| Execution | Continuous* |
| Sequence | None |
| Duration | 10 seconds or more |
*: The malfunction judgment is cleared when it is judged as normal under the same driving conditions in which the malfunction is detected.
| DTC Type | Two drive cycles, MIL on |
*: The malfunction judgment is cleared when it is judged as normal under the same driving conditions in which the malfunction is detected.
Enable Conditions
| Condition | Minimum | Maximum |
|---|---|---|
| Engine coolant temperature [ECT Sensor 1] | 140 deg.F (60 deg.C) | - |
| Idle speed control | Closed loop | |
| Fuel feedback | Closed loop | |
[ ]: HDS Parameter
Malfunction Threshold
The value calculated from the following formula is 25 % or more for at least 10 seconds.
Long fuel trim + (plus) short fuel trim + (plus) (A/F sensor (sensor 1) value - (minus) target air/fuel ratio)
Possible Cause
- EVAP canister purge nozzle disconnection
- Rear A/F sensor (bank 1, sensor 1) failure
- Front A/F sensor (bank 2, sensor 1) failure
- Fuel system failure
- Intake air system failure
Confirmation Procedure
Operating Condition
Start the engine. Hold the engine speed [Engine Speed] at 3, 000 rpm without load (in P or N) until the radiator fan comes on, then let it idle.
Diagnosis Details
Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the PCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC, the freeze data, and the on-board snapshot are stored.
Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive drive cycles in which the engine conditions are similar to the first time the malfunction was detected. The MIL, the Pending DTC, the Confirmed DTC, the freeze data, and the on-board snapshot can be cleared with the scan tool clear command.