P2173

P2173-HIGH AIRFLOW/VACUUM LEAK DETECTED (SLOW ACCUMULATION)



- When Monitored:
Ignition on and engine running with no MAP Sensor DTCs.

- Set Condition:
A large vacuum leak has been detected or the signal voltage for both TP Sensors is stuck at 2.5 Volts and calculated MAP is less than the Gas Flow Adaptation value. One trip fault; the DTC will set within 5 seconds. ETC light will flash.





Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding. Pre-Diagnostic Troubleshooting Procedure.

1. ACTIVE DIAGNOSTIC TROUBLE CODE (DTC)

NOTE: Diagnose and repair any ETC, MAP Sensor, VSS, or 5 Volt supply circuit DTCs before continuing.

1. Start the engine and allow it to reach normal operating temperature.

WARNING: When the engine is operating, do not stand in direct line with the fan. Do not put your hands near the pulleys, belts or fan. Do not wear loose clothing. Failure to follow these instructions may result in possible serious or fatal injury.

2. Using the scan tool, select View DTCs.

Is the status Active for this DTC?

Yes

- Go To 2

No

- Perform the CHECKING FOR AN INTERMITTENT DTC Diagnostic Procedure. Checking for an Intermittent DTC.

2. VACUUM LEAK

NOTE: This DTC is enabled on engines equipped with a plastic intake manifold to limit engine operation if a large vacuum leak should occur.

NOTE: A large vacuum leak is the most probable cause of this DTC.

1. Inspect the intake manifold, power brake booster, and PCV system for any vacuum leaks.
2. Inspect the MAP Sensor and Throttle Body for proper installation.
3. Inspect the engine for any mechanical conditions that can cause improper engine vacuum.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. PCM Verification Test.

No

- Go To 3

3. MAP SENSOR OPERATION
1. Start the engine.
2. With a scan tool, monitor the MAP Sensor voltage.
3. Snap the throttle.

Does the MAP Sensor voltage vary from below 2.0 Volts at idle to above 3.5 Volts at wide open throttle?

Yes

- Go To 5

No

- Go To 4

4. MAP SENSOR
1. Turn the ignition off.
2. Disconnect the MAP Sensor harness connector.
3. Disconnect the PCM harness connector.
4. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the MAP Sensor and the Powertrain Control Module (PCM).
5. Look for any chafed, pierced, pinched, or partially broken wires.
6. Look for broken, bent, pushed out or corroded terminals.
7. Check each of the MAP Sensor circuits for high resistance or a shorted condition.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. PCM Verification Test.

No

- Replace the MAP Sensor.
- Perform the PCM Verification Test. PCM Verification Test.

5. POWERTRAIN CONTROL MODULE (PCM)
1. Using the wiring diagram/schematic as a guide, inspect the wiring and connectors between the MAP Sensor and the Powertrain Control Module (PCM) and between the Throttle Body and the Powertrain Control Module (PCM).
2. Look for any chafed, pierced, pinched, or partially broken wires.
3. Look for broken, bent, pushed out or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

- Repair as necessary.
- Perform the PCM Verification Test. PCM Verification Test.

No

- Replace and program the Powertrain Control Module (PCM).
- Perform the PCM Verification Test. PCM Verification Test.