DTC P0068: Map/MAF - Throttle Position Correlation: Notes

DTC detecting condition: 

Detected when two consecutive driving cycles with fault occur.

1. CHECK AIR INTAKE SYSTEM  .

   Check the installing condition of the air intake system.

   Are there holes, loose bolts or disconnection of hose on air intake system?

   Yes:  Repair the air intake system.

   No:  Go to  2.

2. CHECK MANIFOLD ABSOLUTE PRESSURE SENSOR  .
   1. Start the engine and warm up engine until coolant temperature is higher than 75°C (167°F).
   2. For CVT models, set the select lever to "P" range or "N" range, and for MT models, place the shift lever in the neutral position.
   3. Turn the A/C switch to OFF.
   4. Turn all the accessory switches to OFF.
   5. Using the Subaru Select Monitor or a general scan tool, read the value of [Mani. Absolute Pressure].

      Data Monitor 

      NOTE:

      • SUBARU SELECT MONITOR

        For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR .

      • General scan tool

        For detailed operation procedures, refer to the general scan tool operation manual.

   Is the value of [Mani. Absolute Pressure] 73.3 - 106.6 kPa (550 - 800 mmHg, 21.65 - 31.50 inHg) at ignition ON, and 20.0 - 46.7 kPa (150 - 350 mmHg, 5.91 - 13.78 inHg) at idling?

   Yes:  Go to  3.

   No:  Replace the manifold absolute pressure sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>MANIFOLD ABSOLUTE PRESSURE SENSOR .

3. CHECK THROTTLE OPENING ANGLE  .

   Using the Subaru Select Monitor or a general scan tool, read the value of [Throttle Opening Angle].

   Data Monitor 

   NOTE:

   • SUBARU SELECT MONITOR

     For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR .

   • General scan tool

     For detailed operation procedures, refer to the general scan tool operation manual.

   Is the value of [Throttle Opening Angle] less than 5% when throttle is fully closed?

   Yes:  Go to  4.

   No:  Replace the electronic throttle control. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .

4. CHECK THROTTLE OPENING ANGLE  .

   Using the Subaru Select Monitor or a general scan tool, read the value of [Throttle Opening Angle].

   Data Monitor 

   NOTE:

   • SUBARU SELECT MONITOR

     For detailed operation procedures, refer to "Data Monitor". Ref. to ENGINE (DIAGNOSTICS) (H4DO)>DATA MONITOR .

   • General scan tool

     For detailed operation procedures, refer to the general scan tool operation manual.

   Is the value of [Throttle Opening Angle] 85% or more when throttle is fully closed?

   Yes:  Replace the manifold absolute pressure sensor. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>MANIFOLD ABSOLUTE PRESSURE SENSOR .

   No:  Replace the electronic throttle control. Ref. to FUEL INJECTION (FUEL SYSTEMS) (H4DO)>THROTTLE BODY .