DTC P2187


id010200812500

DTC P2187

System too lean at idle

DETECTION CONDITION

• The PCM monitors short term fuel trim (SHRTFT) and long term fuel trim (LONGFT) during the closed loop fuel control at idle. If the LONGFT and the sum total of these fuel trims and correction exceed the preprogrammed criteria, the PCM determines that the fuel system is too lean during idle.
Diagnostic support note
• This is a continuous monitor. (Fuel system)
• The MIL illuminates if the PCM detects the above malfunctioning condition in two consecutive drive cycles or in one drive cycle while the DTC for the same malfunction has been stored in the PCM.
• The PENDING CODE is available if the PCM detects the above malfunction conditions during the first drive cycle.
• The FREEZE FRAME DATA is available.
• The DTC is stored in the PCM memory.

POSSIBLE CAUSE

• Misfire
• HO2S deterioration
• HO2S heater malfunction
• MAF sensor malfunction
• Pressure regulator (built-in fuel pump unit) malfunction
• Fuel pump malfunction
• Fuel filter clogged or restricted
• Fuel leakage on fuel line from fuel delivery pipe and fuel pump
• Leakage exhaust system
• Purge solenoid valve malfunction
• Purge solenoid hoses improper connection
• Air suction in intake-air system
• Insufficient engine compression
• Variable valve timing control system improper operation
• PCM malfunction

Diagnostic procedure

STEP

INSPECTION

ACTION

1
PERFORM DTC CONFIRMATION PROCEDURE
• Perform the DTC CONFIRMATION PROCEDURE.
• Is the same DTC present?
Yes
Go to the next step.
No
Intermittent concern exists.
Go to the INTERMITTENT CONCERN TROUBLESHOOTING procedures.
2
VERIFY RELATED PENDING CODE OR STORED DTC
• Turn the ignition switch off, then to the ON position (Engine off).
• Verify the related PENDING CODE or stored DTCs.
• Are other DTCs present?
Yes
• If a misfire DTC is present, go to Step 7.
• If any other DTC is present, go to the appropriate DTC inspection.
No
• If a driveability concern is present, go to Step 7.
• If other, go to the next step.
3
IDENTIFY TRIGGER DTC FOR FREEZE FRAME DATA
• Is DTC P2187 displayed in FREEZE FRAME DATA?
Yes
Go to the next step.
No
Go to the FREEZE FRAME DATA DTC inspection.
4
VERIFY CURRENT INPUT SIGNAL STATUS (IGNITION SWITCH TO ON/IDLE)
• Access the ECT, MAF, TP, and VSS PIDs using the WDS or equivalent.
• Is there any signal that is far out of specification during KOER?
Yes
Inspect the suspected sensor for excessive resistance in the related wiring harnesses.
Repair or replace if necessary.
Then go to Step 16.
No
Go to the next step.
5
VERIFY CURRENT INPUT SIGNAL STATUS UNDER TROUBLE CONDITION
• Inspect the same PIDs as Step 3 while simulating FREEZE FRAME DATA condition.
• Is there any signal which causes drastic changes?
Yes
Inspect the suspected sensor and the related wiring harnesses, and repair or replace.
Then go to Step 16.
No
Go to the next step.
6
VERIFY CURRENT INPUT SIGNAL STATUS OF HO2S
• Access the O2S11 PID using the WDS or equivalent.
• Verify the PID under the following accelerator pedal condition (in PARK (ATX) or NEUTRAL (MTX)).
• Is the PID normal?

- Above 0.45 V when the accelerator pedal is suddenly depressed (rich condition)

- Below 0.45 V just after releasing accelerator pedal (lean condition)

Yes
Go to the next step.
No
Visually the inspect for any gas leakage between the exhaust manifold and the HO2S.
Then go to Step 16.
7
INSPECT MAF PID
• Start the engine.
• Access the MAF PID using the WDS or equivalent.
• Verify that the MAF PID changes quickly according to the engine speed.
• Is the MAF PID response normal?
Yes
Go to the next step.
No
Replace the MAF/IAT sensor, then go to Step 16.
8
INSPECT FOR EXCESSIVE AIR SUCTION OF INTAKE AIR SYSTEM
• Visually inspect hoses in the intake-air system for looseness, cracks or damage.
• Is there any malfunction?
Yes
Repair or replace the source of the air suction, then go to Step 16.
No
Go to the next step.
9
INSPECT PURGE SOLENOID VALVE STUCK OPEN
• Turn the ignition switch off.
• Disconnect both hoses from the purge solenoid valve.
• Blow air through the purge solenoid valve.
• Does air blow through?
Yes
Replace the purge solenoid valve.
Then go to Step 16.
No
Go to the next step.
10
INSPECT FUEL LINE PRESSURE
• Turn the ignition switch off.
Note
• If the engine will not start, inspect the fuel line pressure with the ignition switch in the ON position.
• Inspect the fuel line pressure while the engine is running.
• Is the fuel line pressure normal?
Yes
Go to Step 12.
No
If the fuel pressure is too high, replace the fuel pump unit, then go to Step 16.
If the fuel line pressure is low, go to the next step.
11
INSPECT FUEL LINE FROM FUEL PUMP TO FUEL DELIVERY PIPE
• Visually the inspect the fuel line for any leakage.
• Is the any fuel leakage?
Yes
Replace the suspected fuel line, then go to Step 16.
No
Inspect for foreign material or stains inside the fuel filter (low pressure).
• If for foreign material or stains are inside the fuel filter (low pressure), clean the fuel tank and filter, then go to Step 16.
• If for no foreign material or stains are inside the fuel filter (low pressure), go to the next step.
12
INSPECT IGNITION SYSTEM
• Perform the spark test.
• Is a strong blue spark visible at each cylinder?
Yes
Go to the next step.
No
Repair or replace the malfunctioning part according to the spark test results, then go to Step 16.
13
INSPECT ENGINE COMPRESSION
• Inspect the engine compression.
• Is it normal?
Yes
Go to the next step.
No
Perform the engine overhaul for repairs, then go to Step 16.
14
INSPECT VARIABLE VALVE TIMING CONTROL SYSTEM OPERATION
• Inspect the variable valve timing control system operation.
• Does the variable valve timing control system function properly?
Yes
Go to the next step.
No
Repair or replace the malfunctioning parts according to the inspection results, then go to Step 16.
15
INSPECT FUEL INJECTOR OPERATION
• Remove the fuel injector.
• Inspect the fuel injector (resistance, injection amount).
• Is the fuel injector normal?
Yes
Go to the next step.
No
Replace the suspected fuel injector, then go to the next step.
16
VERIFY TROUBLESHOOTING OF DTC P2187 COMPLETED
• Make sure to reconnect all disconnected connectors.
• Clear the DTC from the PCM memory using the WDS or equivalent.
• Perform the KOER self-test.
• Is the same DTC present?
Yes
Replace the PCM, then go to the next step.
No
Go to the next step.
17
VERIFY AFTER REPAIR PROCEDURE
• Perform the "AFTER REPAIR PROCEDURE".
• Are any DTCs present?
Yes
Go to the applicable DTC inspection.
No
DTC troubleshooting completed.