MBE 900 – Section 15.11 Excessive White Smoke

Section 15.11
Excessive White Smoke

There are several causes for excessive white exhaust smoke. These probable causes are:‪

• Faulty DDEC-ECU
• Faulty Turbocharger Boost Sensor
• Malfunctioning Air Intake (Grid) Preheater
• Defective Fuel Pump
• Aerated Fuel
• Improper Grade of Fuel
• Faulty Turbocharger Control Unit
• Restricted or Cracked Charge Air Cooler
• Faulty Fuel Nozzle Holder
• Improper Valve Clearance, Worn or Damaged Camshaft Lobes and Rollers
• Low Cylinder Compression

Section 15.11.1
Troubleshooting Procedure for Faulty DDEC-ECU

To determine if a faulty DDEC-ECU is causing excessive white smoke, perform the following:‪

1. Check for faulty DDEC-ECU. Refer to DDC publication MBE Troubleshooting Guide (6SE422) and SID 233.
2. Replace the faulty DDEC-ECU; refer to "2.5 DDEC-ECU (Engine Control Unit)" .
3. Verify DDEC-ECU replacement; refer to "15.11.2 Test the Engine with Replaced DDEC-ECU" .

Section 15.11.2
Test the Engine with Replaced DDEC-ECU

Perform the following to determine if the replaced DDEC-ECU has resolved the excessive white smoke:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle with a no-load condition for approximately five minutes, allowing the engine coolant to reach normal operating range.
3. Visually inspect the exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessively white, shut down the engine. Refer to "15.11.3 Faulty Turbocharger Boost Sensor" .

Section 15.11.3
Faulty Turbocharger Boost Sensor

To determine if a faulty turbocharger boost sensor is causing excessive white smoke, perform the following:‪

1. Check for faulty turbocharger boost sensor. Refer to DDC publication MBE Troubleshooting Guide (6SE422) and PID 102.
2. Resolve the faulty turbocharger boost sensor; refer to "15.11.4 Turbocharger Boost Sensor Resolution" .

Section 15.11.4
Turbocharger Boost Sensor Resolution

Perform the following steps to resolve a faulty turbocharger boost sensor:‪

1. Disconnect harness connection from turbocharger boost sensor and remove two bolts securing the boost sensor to the air intake manifold. Discard sensor.
2. Secure the turbocharger boost sensor to the air intake manifold with two bolts. Torque bolts to 11 N·m (96 lb·in.).
3. Connect the harness connector to the boost sensor.
4. Verify the turbocharger boost sensor resolution; refer to "15.11.4.1 Test Engine with Replace Turbocharger Boost Sensor" .

Section 15.11.4.1
Test Engine with Replace Turbocharger Boost Sensor

Perform the following to determine if replacing the turbocharger boost sensor corrected the excessive white smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start the engine.
2. Run the engine speed to full load.
3. Visually inspect the exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessive, shut down the engine, check for a malfunctioning air intake (grid) preheater. Refer to "15.11.5 Troubleshooting Procedure for a Malfunctioning Air Intake (Grid) Preheater" .

Section 15.11.5
Troubleshooting Procedure for a Malfunctioning Air Intake (Grid) Preheater

To determine if a malfunctioning air intake (grid) preheater is causing the excessive white smoke, perform the following steps:‪

1. Check the operation of the air intake (grid) preheater. Refer to DDC publication MBE Troubleshooting Guide (6SE422) and PID 45.
   1. If heater operates correctly; check for a defective fuel pump. Refer to "15.11.6 Troubleshooting Procedure for a Defective Fuel Pump" .
   2. If heater does not operate correctly, replace air intake (grid) preheater; refer to "6.1.1 Air Intake Preheater Removal" .
2. Verify replacing the air intake (grid) preheater resolved the excessive white smoke condition; refer to "15.11.5.1 Test the Engine with Replaced Air Intake (Grid) Preheater" .

Section 15.11.5.1
Test the Engine with Replaced Air Intake (Grid) Preheater

Perform the following to determine if replacing the air intake (grid) preheater corrected the excessive white smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start the engine.
2. Run the engine speed to full load.
3. Visually inspect the exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessive, shut down the engine, check for a defective fuel pump. Refer to "15.11.6 Troubleshooting Procedure for a Defective Fuel Pump" .

Section 15.11.6
Troubleshooting Procedure for a Defective Fuel Pump

To determine if the fuel pump is causing excessive white smoke, perform the following to check fuel intake pressure upstream of fuel pump. Refer to "15.3.5 Test #4: Upstream Pressure Test" .‪

1. If the pressure at idle speed (600-650 rpm) is in the normal range of -0.09 to -0.12 bar (-1.3 to -1.7 psi [-9 to -12 kPa]), check for aerated fuel. Refer to "15.11.8 Troubleshooting Procedure for Aerated Fuel" .
2. If the pressure at idle speed (600-650 rpm) is greater than -0.09 to -0.12 bar (-1.3 to -1.7 psi [-9 to -12 kPa]); refer to Table .
3. If the pressure at idle speed (600-650 rpm) is less than -0.09 to -0.12 bar (-1.3 to -1.7 psi [-9 to -12 kPa]); refer to Table
4. If a no pressure reading is observed, replace the fuel pump; refer to "2.15.1 Fuel Pump Removal" .

Section 15.11.7
Replace Faulty Fuel Pump

Perform the following steps for the replacement of the fuel pump:‪

1. Replace the fuel pump; refer to "2.15.1 Fuel Pump Removal" .
2. Test the engine to determine if the white smoke problem was resolved; refer to "15.11.7.1 Engine Test with Replaced Fuel Pump" .

Section 15.11.7.1
Engine Test with Replaced Fuel Pump

To determine if the replaced fuel pump resolved excessive white smoke difficulty, perform the following steps:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine, if no white smoke is visible, no further troubleshooting is required. Shut down the engine.
2. If white smoke is visible, check for aerated fuel; refer to "15.11.8 Troubleshooting Procedure for Aerated Fuel"

Section 15.11.8
Troubleshooting Procedure for Aerated Fuel

To determine if aerated fuel is causing excessive white smoke, perform the following steps:‪

1. Disconnect the fuel line return hose from the fitting located at the fuel tank; refer to OEM guidelines.
2. Place the open end of the fuel line into a suitable container.

   PERSONAL INJURY ‪
   To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

3. Start and run the engine.
4. Operate the engine at 1000 rpm.
5. Visually check to see if air bubbles are rising to the surface of the fuel within the container.
   1. If air bubbles are present, shut down the engine; refer to "15.11.9 Aerated Fuel Resolution" .
   2. If air bubbles are not present, shut down the engine, check for improper grade of fuel; refer to "15.11.10 Troubleshooting Procedure for Improper Grade of Fuel" .

Section 15.11.9
Aerated Fuel Resolution

Perform the following steps to resolve aerated fuel:‪

1. Tighten all fuel line connections between fuel tank and fuel pump; refer to OEM guidelines.
2. Visually inspect all fuel lines between fuel tank and fuel pump for leaks.
3. Repair damaged components as required; refer to OEM guidelines.
4. Verify aerated fuel resolution; refer to "15.11.9.1 Test the Engine with Aerated Fuel Resolution" .

Section 15.11.9.1
Test the Engine with Aerated Fuel Resolution

Perform the following to determine if aerated fuel resolution resolved excessive white smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle with a no-load condition for approximately five minutes, allowing the engine coolant to reach normal operating range.
3. Visually inspect exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessively white, shut down the engine. Check for improper grade of fuel; refer to "15.11.10 Troubleshooting Procedure for Improper Grade of Fuel" .

Section 15.11.10
Troubleshooting Procedure for Improper Grade of Fuel

To determine if an improper grade of fuel is causing the excessive white smoke, perform the following:‪

1. Acquire a fuel sample from the vehicle fuel tank(s).
2. Submit fuel sample for an ASTM test analysis.
   1. If the fuel meets specifications, check for a faulty turbocharger control unit; refer to "15.11.12 Troubleshooting Procedure for Faulty Turbocharger Control Unit" .
   2. If the fuel did not meet specifications, resolve improper grade of fuel; refer to "15.11.11 Improper Grade of Fuel Resolution" and DDC publication Lubricating Oil, Fuel, and Filters (7SE270).

Section 15.11.11
Improper Grade of Fuel Resolution

Perform the following steps to resolve the improper grade of fuel:‪

1. Drain the fuel tanks, refer to OEM guidelines, and dispose of properly.
2. Refill the fuel tanks with new fuel having a cetane number greater than 45 and cetane index greater than 40.
3. Verify fuel resolution eliminated the excessive exhaust smoke condition; refer to "15.11.11.1 Test the Engine with New Fuel" .

Section 15.11.11.1
Test the Engine with New Fuel

Perform the following steps to determine if the fuel refill resolved the excessive white smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle under no-load conditions for approximately five minutes, allowing the engine coolant to reach normal operating range, approximately 88-96°C (190-205°F).
3. Visually inspect exhaust for excessive smoke.
   1. If the engine smoke emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust smoke is excessively white, shut down the engine. Check the turbocharger control unit; refer to "15.11.12 Troubleshooting Procedure for Faulty Turbocharger Control Unit" .

Section 15.11.12
Troubleshooting Procedure for Faulty Turbocharger Control Unit

To determine if an improper turbocharger control unit is causing excessive white smoke, inspect the turbocharger control unit for a leaking diaphragm. Refer to "6.4.1 Inspection" .‪

1. If the control unit diaphragm is leaking replace the turbocharger; refer to "6.4.2 Turbocharger Removal" .
2. Verify the replacement of the turbocharger and unit control corrected the excessive white smoke condition; refer to "15.11.12.1 Test Engine with Replace Turbocharger and Control Unit" .

Section 15.11.12.1
Test Engine with Replace Turbocharger and Control Unit

Perform the following to determine if replacing the turbocharger and control unit corrected the excessive white smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start the engine.
2. Run the engine speed to full load.
3. Visually inspect the exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessive, shut down the engine, check for a restricted or cracked charge air cooler. Refer to "15.11.13 Troubleshooting Procedure for a Restricted or Cracked Charge Air Cooler" .

Section 15.11.13
Troubleshooting Procedure for a Restricted or Cracked Charge Air Cooler

To determine if a charge air cooler is causing excessive exhaust smoke, perform the following:‪

NOTICE:
To avoid engine damage, follow the installation instructions provided with the air-to-air charge air cooler test kit.‪

1. Visually inspect the core, tanks, and welds for cracks and holes. If cooler fails visual inspection, replace the charge air cooler;refer to "15.11.14 Charge Air Cooler Replacement" .
2. Pressure test the charge air cooler.Refer to "15.9.3.1 Pressure Testing the Charge Air Cooler" .
3. Evaluate the results from pressure testing the charge air cooler.
   1. If the pressure drop is 34 kPa (5 psi) or less in 15 seconds the cooler is good. Check for faulty fuel injection nozzle; refer to "15.11.15 Troubleshooting for a Faulty Fuel Injection Nozzle Holder" .
   2. If the pressure drop is greater than 34 kPa (5 psi) in 15 seconds, replace the charge air cooler; refer to "15.11.14 Charge Air Cooler Replacement" .

Section 15.11.14
Charge Air Cooler Replacement

Perform the following steps to replace the charge air cooler:‪

1. Replace the charge air cooler; refer to OEM guidelines.
2. Verify that the replacement of the charge air cooler eliminated the excessive white exhaust smoke; refer to "15.11.14.1 Test the Engine with a Replaced Charge Air Cooler" .

Section 15.11.14.1
Test the Engine with a Replaced Charge Air Cooler

To determine if the replaced charge air cooler resolved the excessive white exhaust smoke condition, perform the following:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle with a no-load condition for approximately five minutes, allowing the engine coolant to reach normal operating range, approximately 88-96°C (190-205°F).
3. Visually inspect exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessively white, shut down the engine. Check for a faulty fuel injection nozzle holder; refer to "15.11.15 Troubleshooting for a Faulty Fuel Injection Nozzle Holder" .

Section 15.11.15
Troubleshooting for a Faulty Fuel Injection Nozzle Holder

To determine if a faulty fuel injection nozzle holder is causing excessive white smoke, perform the following:‪

1. Check for faulty fuel injection nozzle holder; perform “Flow Test at Nozzle Holder”. Refer to "15.3.3 Test #2: Flow Test — At Nozzle Holder" .
2. Repair or replace the faulty fuel injection nozzle holder; refer to "2.3.1 Nozzle Holder Removal" .
3. Verify fuel injection nozzle holder repair or replacement; refer to "15.11.15.1 Test the Engine with Repaired Fuel Injection Nozzle Holder" .

Section 15.11.15.1
Test the Engine with Repaired Fuel Injection Nozzle Holder

To determine if a faulty fuel injector nozzle holder is causing excessive white smoke, perform the following:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle with a no-load condition for approximately five minutes, allowing the engine coolant to reach normal operating range, approximately 88-96°C (190-205°F).
3. Visually inspect exhaust for excessive white smoke.
   1. If the engine exhaust emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust emission is excessively white, shut down the engine. Check for improper valve clearance or damaged camshaft lobes and rollers; refer to "15.11.16 Troubleshooting Procedure for Improper Valve Clearance, Worn or Damaged Camshaft Lobes and Rollers" .

Section 15.11.16
Troubleshooting Procedure for Improper Valve Clearance, Worn or Damaged Camshaft Lobes and Rollers

To determine if an improper valve clearance, worn or damaged camshaft lobes or rollers are causing excessive white exhaust smoke, perform the following:‪

1. Check for improper valve clearance, and worn or damaged camshaft lobes and rollers. Repair as required. Refer to "1.17.2 Checking Valve Lash" and section "1.20 Camshaft" .
2. Verify valve clearance, worn or damaged camshaft lobes and rollers repair corrected the excessive white exhaust smoke concern; refer to "15.11.16.1 Test Engine with Corrected Valve Clearance, Worn or Damaged Camshaft Lobes and Rollers" .

Section 15.11.16.1
Test Engine with Corrected Valve Clearance, Worn or Damaged Camshaft Lobes and Rollers

Perform the following steps to determine if the valve clearance, worn or damaged camshaft lobes and rollers repair has resolved excessive white exhaust smoke condition:‪

PERSONAL INJURY ‪
To avoid injury before starting and running the engine, ensure the vehicle is parked on a level surface, parking brake is set, and the wheels are blocked. ‪

1. Start and run the engine.
2. Run the engine at idle with a no-load condition for approximately five minutes, allowing the engine coolant to reach normal operating range.
3. Visually inspect exhaust for excessive white exhaust smoke.
   1. If the engine exhaust smoke emission appears normal, no further troubleshooting is required. Shut down the engine.
   2. If the engine exhaust smoke emission is excessive, shut down the engine. Check for low cylinder compression; refer to "15.11.17 Troubleshooting for Low Cylinder Compression" .

Section 15.11.17
Troubleshooting for Low Cylinder Compression

To determine if low compression is causing excessive white smoke condition, perform the following steps:‪

1. Perform a cylinder compression test;refer to "1.2.2.2 Compression Testing" .
2. Compare cylinder compression test results to specifications as listed in Table "Compression Testing Specifications" .

   Description‪	Pressure in kPa (psi)‪
   Compression Pressure at Starter Speed‪	2800 (406)‪
   Permissible Difference between Individual Cylinders‪	400 (58)‪

   Table 13. Compression Testing Specifications
   1. If cylinder pressure is below specifications, refer to "15.5.28 Low Compression Repair" .
   2. If cylinder pressure is within specifications, call Detroit Diesel Customer Support Center at 313-592-5800.