Inspection of the EPA10 and Newer Exhaust System

p3 mm 49.01.002

To meet EPA10 emissions regulations for vehicles domiciled in the USA or Canada, engines manufactured after December 31, 2009 are equipped with an emission aftertreatment system. Vehicles domiciled outside of the USA and Canada may not have aftertreatment equipment, depending upon local statutory emissions guidelines.

    Important: The aftertreatment device (ATD), which is part of the aftertreatment system (ATS), requires special attention during regularly scheduled maintenance inspections. No leaks are allowed anywhere in the system. If any discrepancies are discovered, refer to the engine manufacturer's service literature for repair instructions.

  1. Check for leakage at the clamp that attaches the exhaust pipe to the turbocharger exhaust outlet. If leakage exists, tighten the nut on the clamp to the required torque. If leakage persists, install a new clamp.
  2. Check the exhaust pipe, bellows, and each exhaust seal clamp for leakage, wear, cracks, or damage. Replace damaged components as needed. If leakage exists at a clamp, tighten the nuts to the required torque. If leakage persists, install a new exhaust seal clamp. Do not reuse seal clamps. Once a seal clamp is loosened or removed, it must be replaced.
  3. If present, check the condition of the insulation material around the exhaust pipe between the turbocharger and the ATD.
  4. Check the ATD mounting bands for tightness. Tighten to 30 lbf·ft (41 N·m) if needed. Do not overtighten.
  5. Check for leaks around the clamps that attach the ATD in the ATS, and around the clamps that retain the DPF in the ATD.
  6. Check all sensors attached to the ATS for leaks or damaged wires. No leaks are allowed. See Fig., Fig., or Fig. for Detroit Diesel ATS sensor locations.
  7. Check the DPF exterior surface for dents or other damage. A dent over 3 inches (76 mm) in diameter and 1/4-inch (6-mm) deep could cause internal damage to the DPF, causing it to malfunction.

    Note: The sensor box (item 11) contains the SCR outlet NOx and PM sensors, and the Aftertreatment Control Module (ACM).

    1. DOC Inlet NOx Sensor

    2. DOC Inlet Pressure Sensor

    3. DOC Inlet NOx Sensor Port

    4. Exhaust Inlet

    5. 18-Pin Connectors

    6. Particular Matter Sensor Port

    7. SCR Outlet Temperature Sensor

    8. SCR Outlet NOx Sensor Port

    9. Exhaust Outlet

    10. DEF Metering Unit

    11. Sensor Box (see note above)

    12. DPF Outlet Temperature Sensor

    13. DOC Inlet Temperature Sensor

    14. DOC Inlet Pressure Sensor Port

    15. DOC Outlet Temperature Sensor

    16. Front Heat Shield

    Fig. 1, One-Box ATS Sensor Locations

  8. Check the SCR catalyst for dents and other damage.
  9. Check for heat discoloration on the surface of the ATD. Heat discoloration may indicate internal damage; especially around the DPF.

    1. DEF Metering Unit

    2. SCR Outlet Temperature Sensor

    3. SCR Inlet Temperature Sensor

    4. DOC Inlet Temperature Sensor

    5. DOC Inlet Pressure Sensor

    6. DPF Inlet Temperature Sensor

    7. Particulate Matter Sensors

    8. DPF Outlet Pressure Sensor

    9. DPF Outlet Temperature Sensor

    10. DPF Outlet NOx Sensor

    11. SCR Outlet NOx Sensor

    Fig. 2, 2V2 Two-Box ATS Sensor Locations

    1. DPF Inlet Temperature Sensor

    2. DOC Inlet Temperature Sensor

    3. DOC Inlet Pressure Sensor

    4. DPF Sensor Box

    5. DPF Outlet Pressure Sensor

    6. DPF Outlet Temperature Sensor

    7. DPF Outlet NOx Sensor

    8. SCR Inlet Temperature Sensor

    9. SCR Outlet Temperature Sensor

    10. SCR Sensor Box

    11. SCR Outlet NOx Sensor

    Fig. 3, 2HV Two-Box ATS Sensor Locations

    10. Note: Diesel exhaust fluid creeps, causing white crystals to form around the line fittings. The presence of crystals does not mean the system has a leak. Replacing fittings or troubleshooting components is not necessary unless there is a system failure or a fault code.

  10. Check the DEF tank, pump, metering unit, and lines for leaks. See of the Cascadia™ Workshop Manual for repair procedures.
  11. Check any wires, lines, or hoses within 4 inches (10 cm) of the exhaust system for heat damage. Repair or reroute as needed.
Note:
Parent topic: EPA10 and Newer Exhaust System
Document Number: 0000116551
Manual Publication Date: 2024-05-15
Topic Publication Date: 2024-11-22