Checking The Exhaust System For Leaks

CHECKING THE EXHAUST SYSTEM FOR LEAKS 

1. Turn the ignition off.
2. Raise the vehicle in accordance with the service information.
   WARNING:

   The normal operating temperature of the exhaust system is very high. Never work around or attempt to service any part of the exhaust system until it has cooled. Special care should be taken when working near the catalytic converter. The temperature of the converter rises to a high level after a short period of engine operating time.

3. Connect the (special tool #8404-ECT, Exhaust Cone, Truck) to the Air Pressure Regulator (with hose) W-18-MIL-1146AS.
   CAUTION:

   The air pressure must not exceed 4 psi, otherwise engine damage can occur.

4. Attach shop air to the air pressure regulator.
5. Adjust the Air Pressure Regulator to 4.0 psi.
6. Insert the exhaust cone into the vehicle tail pipe.
7. If the vehicle is equipped with dual exhaust. Use the (special tool #8404-ECT, Exhaust Cone, Truck) with equipped attached plug, plug one side of the dual exhaust pipe. Pressurize the other as described above.
8. Apply Mopar Air Leak Detector or Equivalent to the following areas:
   • Particulate Matter Sensor seal points (where applicable).
   • Particulate Matter Sensor boss welds (where applicable).
   • NOx Sensor 1 seal points (where applicable).
   • NOx Sensor 1 boss welds (where applicable).
   • NOx Sensor 2 seal points (where applicable).
   • NOx Sensor 2 boss welds (where applicable).
   • Flange/joint connection(s).
   • Exhaust Manifold to Cylinder Head connection(s).
   • EGR Solenoid gasket base and tube seal points (if equipped).
   • Watch for the liquid/soapy water to bubble.
9. Use the following definitions to help determine if system or component repair/replacement is necessary:
   • Type 1 Leak  is defined as a leak where very small foam like bubbles (1.0 mm or less) appear.

     Any Type 1 or greater leaks found in welded joints: NOx Sensor 1 - NOx Sensor 2 seal points or NOx Sensor 1 - NOx Sensor 2 boss welds must be repaired or the component must be replaced.

   • Type 2 Leak  is defined as a leak where larger bubbles (pea size, 8.0 mm or greater) appear.

     Any Type 2 or greater leaks found in welded joints: NOx Sensor 1 - NOx Sensor 2 seal points or NOx Sensor 1 - NOx Sensor 2 boss welds must be repaired or the component must be replaced.

   Leak Location	Repair required if results at 4 psi reveal bubble size:
   Welded joints	Type 1 (1.0 mm) or greater
   Particulate Matter Sensor seal points	Type 1 (1.0 mm) or greater
   NOx Sensor 1 seal points	Type 1 (1.0 mm) or greater
   NOx Sensor 2 seal points	Type 1 (1.0 mm) or greater
   Particulate Matter Sensor boss welds	Type 1 (1.0 mm) or greater
   NOx Sensor 1 boss welds	Type 1 (1.0 mm) or greater
   NOx Sensor 2 boss welds	Type 1 (1.0 mm) or greater
   Flange / joint connections	Type 2 (8.0 mm) or greater
   Exhaust Manifold to cylinder head connections	Type 2 (8.0 mm) or greater
   EGR gasket and tube seal points	Type 2 (8.0 mm) or greater

10. If a leak is found that matches the above definition, repair or replace the component as necessary.
11. Once the repair is complete, repeat the procedure to verify that all leaks have been repaired.

    Were any exhaust leaks found?

    Yes 

    • Repair or replace the leaking exhaust parts as necessary.
    • Perform the POWERTRAIN VERIFICATION TEST - 6.7L. Refer to POWERTRAIN VERIFICATION TEST - 6.7L .

    No 

    • Test complete.