Identify the Cause fo a Noisy 1-BOX Aftertreatment for Detroit Diesel GHG14

This instruction show you guide on how to identify the cause of a Noisy 1-BOX aftertreatment for Detroit Diesel EPA01 10 GHG14 engine.

 

Related Contents:

2024.06 Detroit Diesel Diagnostic Link DDDL 8.20 8.09 Free Download

JPRO DLA+ 2.0 Adapter

NEXIQ USB Link Adapter

 

Steps:

1 Visually inspect the entire exhaust system for signs of leaks or damage. Is any damage found?

1a Yes; repair as necessary.

1b No; Go to step 2.

 

2 Inspect that the aftertreatment inlet heat shields are not broken loose and rattling. Is there a loose or damaged heat shield?

 

2a Yes; repair the heat shield. If the inlet heat shield has tabs, refer to 11 TS-6 .

2b No; Go to step 3.

 

3 Inspect the inboard and outboard Diesel Particulate Filter (DPF) covers and verify nothing is loose or rattling. Is there a loose DPF cover?

 

3a Yes; repair the loose cover.

3b No; Go to step 4.

 

4 Turn off engine after inspection.

 

5 Disconnect the aftertreatment inlet pipe and start the engine to verify the noise is coming from the aftertreatment. Did the noise go away once the aftertreatment inlet pipe was disconnected?

5 a Yes; reconnect the aftertreatment inlet pipe and Go to step 6.

5 b No; inspect other truck components to identify the noise.

 

6 Connect DiagnosticLink 8.18.

7 Start the engine and run a Parked Regen. Monitor Diesel Oxidation Catalyst (DOC) inlet pressure and engine speed during the regen.

8 Review the last seven minutes of the parked regeneration log data. The illustration below identifies the last seven minutes of the parked regen.

 

 

9 Is the Selective Catalyst Reduction (SCR) inlet temperature lower than SCR outlet temperature by more than 38°C (68.4°F)?

Example : SCR Outlet temp 587°C (1090°F) minus SCR Inlet Temp 398°C (749°F) = 116°C (241°F). The difference between inlet and outlet temperature is 116°C (241°F), which is greater than 20.2°C (68.4°F).

 

9a Yes; Go to step 10.

9b No; Go to step 11. for log file review.

 

10 Perform a low temperature Aftertreatment Device (ATD) check using DiagnosticLink to check for a drifted temperature sensor. Are the SCR inlet and SCR outlet temperatures within 25°C (45°F) during the last five minutes of this test?

 

10a Yes; replace the DOC/SCR module. This indicates internal structural damage; see image below. The ATD checklist is NOT required since the ATD is the primary failed part.

10b No; replace the drifted SCR temperature sensor and Go to step 11.

 

11 Review the parked regen log file. Compare your DOC inlet pressure reading to the screen shots below (steps 12, 13, and 14) to identify a possible cause of the aftertreatment noise.

 

12 Is the DOC Inlet Pressure starting out high above 10 kPa (1.45 psi) and decreases during a parked regen?

12a Yes; Go to step 15.

12b No; Go to step 13.

DOC inlet pressure (orange line) started at 16kPa (2.32 psi) and dropped to 5kPa (0.72 psi) during a full regen.

 

13 Is the DOC inlet pressure starting above the pressure specified below and stays high?

DOC inlet pressure (orange line) started at 6 kPa (0.87 psi) and stayed there throughout the regen. The slight spikes seen in the pressure reading are due to the fan turning on/off.

14 When the DOC inlet pressure starts out low and stays low , below 3.1 kPa (.45 psi), the Aftertreatment System (ATS) is considered noisy. Replace the DOC/SCR module. This indicates internal structural damage; see image below. The ATD checklist is NOT required since the ATD is the primary failed part. Verify repair.

15 This indicates that the DPFs were plugged and the parked regen has cleared them. Verify the noise is gone and complete the ATD check list to possibly identify why the unit was plugged.

For EPA10: Refer to section “EPA10 Perform Performance Check – Low Temperature ATD”

For GHG14: Refer to section “GHG14 Perform Performance Check – Low Temperature ATD”

 

16 The DOC is considered plugged. Since the DOC inlet pressure stayed steady and there is still a noise, run the DOC Face Unplugging procedure in DiagnosticLink under Actions-Aftertreatment. Refer to section “EPA10 and GHG14 Diesel Oxidation Catalyst Face Cleaning” . After completing the service routine, verify the noise is gone. Go to step 17.

 

17 Review DDEC reports to find out if excessive engine idle time is the cause of the plugged DOC. Refer to section “How to Retrieve DDEC Reports” . If the vehicle exhibits high idle time refer to Warranty letter 15-049R .

 

18 The DOCs are severely face plugged. Refer to section “Diesel Oxidation Catalyst Air Cleaning” . After cleaning, verify the noise is gone and release the vehicle.

 

More repair cases for Detroit Diesel engines,please refer to:Detroit Diesel Engine Repair