EXHAUST HEAT RECIRCULATION SYSTEM ON-VEHICLE INSPECTION

PROCEDURE

1. INSPECT CENTER EXHAUST PIPE ASSEMBLY

   
   

   1. Inspect exhaust flow control valve operation.

      
      

      1. 

         Using a screwdriver, move the exhaust flow control valve from underneath the vehicle. Check that the valve moves smoothly.

         OK
         Valve moves smoothly.

      2. If the valve is stuck or does not move smoothly, replace the center exhaust pipe assembly (for front side).

         Click here

         Note

         When removing or installing the exhaust pipe gas control actuator, do not subject the temperature switch to impacts.

   2. Inspect the exhaust pipe gas control actuator.

      
      

      1. Connect the GTS to the DLC3.

      2. Turn the ignition switch to ON and turn the tester on.

      3. Enter the following menus: powertrain / Engine and ECT / Data List / Coolant Temp.

         
         Powertrain > Engine and ECT > Data List

         Tester Display
         Coolant Temp

      4. 

         While checking the engine coolant temperature with the GTS, check the operation of the exhaust pipe gas control actuator rod when the temperature rises.

         Standard
         Condition Rod Operation Cold (below approximately 71°C (160°F)) → Warmed up (approximately 80°C (176°F) or more) Rod gradually extends as the temperature rises.

         Tech Tips

         
         

         • After the engine has warmed up (the thermostat temperature is approximately 80°C (176°F) or more), the rod should be extended approximately 7.2 mm (0.284 in.) or more compared to when the engine is cold (the thermostat temperature is below 71°C (160°F)).

         
         

         • The engine coolant temperature shown in the Data List may slightly deviate from the thermostat temperature. This is because the Data List value indicates the temperature detected by the engine coolant temperature sensor, which is mounted on the engine, while the thermostat is positioned in the exhaust pipe gas control actuator.

         
         

         • If it is difficult to check the operation of the rod, allow the engine to cool down until the water temperature matches the ambient temperature and then check for the rod operation again.

      5. If the exhaust pipe gas control actuator rod does not move smoothly, replace the exhaust pipe gas control actuator.

         Click here

      6. Check for any cracks or damage on the exhaust pipe gas control actuator rod.

         OK
         No cracks or damage is found.

      7. If any cracks or damage is found, replace the center exhaust pipe assembly (for front side).

         Click here

2. INSPECT FOR ENGINE COOLANT LEAK FROM CENTER EXHAUST PIPE ASSEMBLY

   CAUTION:

   Do not remove the radiator cap while the engine and radiator are still hot. Pressurized, hot engine coolant and steam may be released and cause serious burns.

   Note

   Be sure to turn the A/C switch off before starting the following inspection.

   
   
   1. 

      *a	Radiator Cap Tester

      Turn the ignition switch off. Check for engine coolant leaks from the center exhaust pipe assembly and the heater hose around the water temperature switch.

   2. Add engine coolant to the radiator and install the radiator cap tester.

   3. Pump it to 108 kPa (1.1 kgf/cm², 16 psi), then check that the pressure does not drop.

      If the pressure drops, check for leaks from the center exhaust pipe assembly or the heater hose around the water temperature switch.