Test Description
The numbers below refer to the step numbers on the diagnostic table.
- 2:
This step determines if there is a current condition.
- 4:
Disconnecting the MAF sensor determines if the MAF sensor signal is skewed. If the Short Term FT parameter changes more than the specified value, there is a condition with the MAF sensor. A MAF sensor condition can cause this DTC without setting a MAF DTC. If there is a MAF sensor condition, the MAF sensor parameters will appear to be within range.
- 5:
Inspect all areas of the engine for a vacuum leak. Also inspect the positive crankcase ventilation (PCV) valve for being the correct one for this application. Make sure that the engine oil fill cap is in place and that it is tight. Verify that the engine oil dip stick is fully seated.
DTC P2187
| Step |
Action |
Values |
Yes |
No |
| 1 |
Did you perform the Diagnostic System Check - Vehicle? |
- |
Go to Step 2 |
Go to Diagnostic System Check - Vehicle |
| 2 |
IMPORTANT:
If any DTCs are set, except P2187, refer to those DTCs before proceeding with this diagnostic.
- Idle the engine at the normal operating temperature.
- The fuel system is in Closed Loop.
- Observe the Total Fuel Trim Avg. parameter with a scan tool.
Is the Total Fuel Trim Avg. less than the specified value indicated? |
40% |
Go to Step 3 |
Go to Step 4 |
| 3 |
- Observe the Freeze Frame and/or the Failure records data for this DTC.
- Turn the ignition OFF for 30 seconds.
- Start the engine.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame and/or the Failure records data.
Does the DTC fail this ignition cycle? |
- |
Go to Step 4 |
Go to Diagnostic Aids |
| 4 |
- Start the engine.
IMPORTANT:
Additional DTCs set with the mass air flow (MAF) sensor disconnected.
- Disconnect the MAF sensor harness connector while the engine is operating.
- Observe the Short Term FT parameter with a scan tool.
- Connect the MAF sensor after completing this step.
Does the Short Term FT parameter change more than the specified value with the MAF sensor disconnected? |
20% |
Go to DTC P0101 |
Go to Step 5 |
| 5 |
Inspect for the following conditions:
- Inspect the vacuum hoses for splits, kinks, and proper connections. Refer to Emission Hose Routing Diagram
.
- Inspect the throttle body and the intake manifold for vacuum leaks.
- Inspect the crankcase ventilation valve and system for leaks.
- Inspect the air intake system after the MAF sensor for vacuum leaks.
- Inspect for exhaust leaks, missing or loose exhaust hardware. Refer to Symptoms - Engine Exhaust
.
- Inspect that the heated oxygen sensor (HO2S) is installed securely and the electrical connector is not contacting the exhaust system.
- Inspect for contaminated fuel. Refer to Alcohol/Contaminants-in-Fuel Diagnosis (w/o Special Tool)
or Alcohol/Contaminants-in-Fuel Diagnosis (w/Special Tool)
.
- Inspect for lean injectors. Refer to Fuel Injector Solenoid Coil Test
.
- Inspect the engine control grounds for being clean, tight, and in the correct locations.
- Inspect for a high engine oil level condition. A high engine oil level causes oil residue to form on the MAF sensor, causing a lean indication. The MAF sensor does not need to be replaced.
- Inspect for an engine mechanical condition. Refer to Symptoms - Engine Mechanical
.
Did you find and correct the condition? |
- |
Go to Step 6 |
Go to Fuel System Diagnosis |
| 6 |
- Turn OFF the ignition for 30 seconds.
- Start the engine.
- Reset the fuel trim system with a scan tool.
- Operate the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records.
Did the DTC fail this ignition? |
- |
Go to Step 2 |
Go to Step 7 |
| 7 |
Observe the Capture Info with a scan tool.
Are there any DTCs that have not been diagnosed? |
- |
Go to Diagnostic Trouble Code (DTC) List - Vehicle |
System OK |