Fulltext TSBs

Technical Service Bulletins

TSB
06-4-12
  • COKING DEPOSIT DIAGNOSTICS AND SERVICE TIPS – 6.0L DIESEL
Publication Date: February 22, 2006

FORD:
2003-2005 Excursion
2003-2006 F-Super Duty
2004-2006 E-Series

ISSUE:

Some vehicles equipped with a 6.0L DI engine may exhibit white smoke, black smoke, lacks power, exhaust odor, surges, or no start as a result of excessive coking deposits (un-combusted or incompletely combusted hydrocarbons), the root cause of the coking must be corrected or the coking may reoccur.

ACTION:

This TSB is to be used only if one or more of the components listed below in the Service Procedure have already been identified as having an excessive coking condition. After following normal Powertrain Controls/Emissions Diagnosis (PC/ED) diagnostics, use this TSB to identify the root cause of the excessive coking condition. Just replacing the component with coking deposits will not correct the root cause, and coking will reoccur. The following steps are Service Tips to determine the source of coking deposits.

SERVICE TIPS

Coking deposits are generally un-combusted or incompletely combusted hydrocarbons and can form on system components such as the EGR valve, EGR cooler, EBP Sensor, EBP tube, intake manifold, turbo charger, catalytic converter and EGR throttle plate. Deposit sample analysis from warranty return parts confirms the source as engine oil or diesel fuel. Visual inspection CAN NOT link the sources of coking deposits as either from engine oil or diesel fuel. Coking deposits can be identified as shiny black grease like sludge, hard flat black solid mass, or thin light brown sticky layer.

Un-combusted deposits can be linked to delayed combustion events. Delayed combustion events can be a function of hard to ignite elements (poor quality fuel, excessive fuel, engine oil or excessive exhaust gas recirculation) in the combustion chamber or a delayed injection event (calibration, wire chafe, injector mechanical issue). Un-combusted fuel is usually evident as fuel scented white exhaust smoke. Un-combusted fuel may create coking which impairs system functionality eventually leading to black exhaust smoke / poorly combusted fuel.

SERVICE PROCEDURE

NOTE:VEHICLE PERFORMANCE ISSUES RELATED TO FUEL QUALITY, MAINTENANCE AND AFTERMARKET MODIFICATIONS ARE NOT COVERED BY FORD MOTOR COMPANY WARRANTY.

Complete all of the following steps. Devices such as the EGR Valve, Turbocharger, Catalyst, MAP sensor and EBP sensor that fail the PC/ED pinpoint tests, must be replaced and not cleaned. Mechanically clean components such as the intake manifold and EBP tube. Install a new component if the cost of cleaning exceeds the replacement value.

  1. Follow PC/ED led diagnostics for any specific drivability issues and DTCs.
  2. Check OASIS for open FSAs and complete before continuing with this TSB.
  3. Validate clean good fuel.
    1. Use PC/ED, Section 4: Diagnostic Subroutines Performance Diagnostic Procedures / Sufficient Clean Fuel.
    2. Use “Diesel Cetane Boost and Performance Improver” Motorcraft PM-17-A (PM-17-B Canada), or “Diesel Fuel Anti-gel and Performance Improver” Motorcraft PM-18-A (PM-18-B Canada) to see if symptoms improve. Motorcraft fuel conditioner will typically reduce white smoke related to fuel quality within 20 miles of driving. Continued use of Diesel Cetane improver will aid in the removal of fuel quality related coking deposits.
  4. Review vehicle maintenance history/records. Refer to the Owner Guide for recommended service intervals and oil grade/viscosity based on vehicle use and ambient temperature. Calculate engine operating hours versus odometer accumulation when selecting appropriate maintenance schedule. (2005 MY and forward are equipped with an hour meter as part of the odometer) Ensure the proper maintenance schedule and oil viscosity/grade is in use. Oil additives that thicken engine oil and poor maintenance can delay commanded injector response. Several oil changes with driving cycles may be required to “flush” the engine of residual additives and/or degraded oil.
  5. Check for excessive oil carryover to air inlet system.
    1. Validate proper air intake flow. Check air filter minder by performing PC/ED Section 4: Diagnostic Subroutines / Performance Diagnostic Procedures / Intake Restriction. Excessive inlet restriction may cause oil carryover from crankcase vent.
    2. Validate crankcase pressure by performing PC/ED Section 4: Diagnostic Subroutines / Performance Diagnostic Procedures / Crankcase Pressure Test. Repair base engine concern if pressures exceed spec.
    3. Validate no internal turbo oil leak by referring to Workshop Manual, Section 303-04D.
  6. Validate fuel pressure is not less than 45 psi, and inlet restriction no more than 6 inches Hg when performing a 0-50 MPH (0-80 Km/h) wide open throttle (WOT) acceleration .
  7. Ensure proper operation of engine cooling system and visctronic fan clutch. Refer to Workshop Manual, Section 303-03 and Section 5, pinpoint test AH of the PC/ED. Repair as necessary if any concerns are found.
  8. Ensure WDS calibration level B36.10 or later is installed, these calibrations include the following improvements which will effect component coking:
    • Shut off EGR after 5 minutes of idling. Reduces the amount of hard to combust elements in the combustion chamber
    • Injection timing improvements @ 1100-1800 RPM (Typical range for PTO operation / Cold Ambient Protection Idle Kicker / Battery Charge Protect Idle Kicker)
    • Increased exhaust pressure / VGT Duty Cycle for APCM or PTO commanded engine speeds. Maintains heat in the combustion chamber
    • Higher engine temperature required for cold ambient idle kicker to switch off. Idle will remain elevated until driver input is observed by powertrain control module (PCM). Maintains heat in the combustion chamber
    • Improved EGR throttle plate self test. Better control of hard to combust elements
    • Validate individual cylinder performance / Validate EGR and Boost system performance.

    NOTE:COKING DEPOSITS ON THE EGR VALVE ALONE IS NOT REASON FOR REPLACEMENT OF THE PART. VALVE REPLACEMENT IS ONLY NECESSARY IF THE VALVE DOES NOT PASS THE FOLLOWING TESTS OR IF THE UPPER VALVE CHAMBER IS MORE THAN 50% RESTRICTED. ONCE THE SOURCE FOR COKING DEPOSITS IS REMEDIED, NORMAL DRIVING WILL REMOVE EXCESSIVE DEPOSITS. DIESEL CETANE BOOST AND PERFORMANCE IMPROVER ADDED TO THE FUEL TANK WILL ACCELERATE THE REMOVAL OF COKING DEPOSITS UNDER NORMAL DRIVING CONDITIONS.

    1. Perform WDS Power Balance Test after overnight cold soak.
      1. Verify engine coolant temperature (ECT) is no lower than 20 F (-7 C), or greater than 50 F (10 C). Accurate test readings can not be achieved when engine ECT is below 20 F (-7 C). The block heater may be used to increase coolant temperature if ECT is lower than 20 F (-7 C). ECT above 50 F (10 C) may limit concern severity and diagnosis time.
      2. Using WDS/IDS, KOEO, set up to start the Power Balance Test.
      3. Turn the key off (reset ignition switch to trigger glow plug cycle).
      4. Key On Engine Running (KOER) – Start the Power Balance test (Monitor only 5-8 seconds before proceeding to Step 5) and record low contributing cylinders (anything below -15).
      5. While still running the Power Balance Test with the idle compensation strategy disabled (# sign pressed), increase the engine speed to between 800-900 RPM (monitor only 5-8 seconds before proceeding to Step 6) record low contributing cylinders (below -15).
      6. Use the results from Steps 4 and 5 to repair the vehicle as necessary.
    2. Perform 2006 MY online PC/ED pinpoint test KA11 immediately following overnight cold soak and performing step 1 above.
    3. Perform WDS Power Balance Test at engine operating temperature. Refer to PC/ED Section 3 for diagnostics related to failed WDS Power Balance Tests in steps 1 and 3.
    4. Review and perform PC/ED pinpoint test KA. If pinpoint test did not lead to KA11, perform KA11 after getting engine up to operating temperature (set transmission in neutral, set parking brake, using WDS/IDS datalogger command RPM above 1100 and command VGT to 85% for 15 minutes)
    5. Review and perform PC/ED pinpoint test X.
  9. Inspect for possible wire chafe(s) in the under hood sensor harness and (Fuel Injector Control Module) FICM harness. With the Key On Engine Running (KOER) – Push wires towards ground and wiggle test connectors. Shifted signals and commands caused by wiring issues may cause increased exhaust pressure resulting in increased exhaust gas recirculation flow rate, which will effect combustion.

PART NUMBERPART NAME
PM-17-AMotorcraft Diesel Cetane Boost And Performance Improver
PM-18-AMotorcraft Diesel Fuel Anti-gel and Performance Improver

WARRANTY STATUS:

Eligible Under Provisions Of New Vehicle Limited Warranty Coverage

OPERATIONDESCRIPTIONTIME
MT060412Claim Additional Labor Required As Actual Time Or Use SLTS Operation If Available:Actual Time

DEALER CODING

BASIC PART NO.CONDITION CODE
9F45242