Engine Controls - Cylinder Contribution Diagnostics
TSB 08-16-708/18/08
CYLINDER CONTRIBUTION DIAGNOSTICS - 6.4L
DIESEL ENGINE - SERVICE TIP
FORD:
2008 F-Super Duty
ISSUE
Some 2008 F-Super Duty vehicles equipped with a 6.4L diesel engine may exhibit a low cylinder contribution event with or without a cylinder contribution or related diagnostic trouble code (DTC) when diagnosing with the Power Balance mode using the IDS or equivalent scan tool.
ACTION
Follow the Service Procedure steps to correct the condition.
SERVICE PROCEDURE
Diagnose and address any driveability issues or hard fault DTCs as would normally be performed. If the diagnosis requires you to use IDS tool to perform power balance diagnostics and a cylinder contribution occurrence exists (witnessed on any cylinder or cylinders) then proceed with the following Service Procedure.
NOTE
THE CYLINDER CONTRIBUTION TEST OR ENHANCED POWER BALANCE MUST BE PERFORMED WHILE THE VEHICLE IS STATIONARY AND NOT IN MOTION. AT NO TIME SHOULD MANUAL INPUT THROUGH THE ACCELERATOR PEDAL (AP) OCCUR DURING THESE TESTS. DO NOT PERFORM THESE TESTS WHILE DRIVING.
NOTE
THE SERVICE PROCEDURE STATED BELOW REQUIRES THE DIAGNOSTICS TO BE PERFORMED AT IDLE ENGINE SPEED. CUSTOMER CONCERNS THAT ARE CLAIMED TO BE EXPERIENCED AT OFF-IDLE ENGINE SPEEDS OR UNDER LOAD CONDITIONS WILL BE ADDRESSED IN STEP 2 OF THIS SERVICE PROCEDURE.
1. With KOER at idle engine speed use the IDS and proceed to the Power Balance Test.
a. On the main power balance screen evaluate each cylinders' performance to specification +/- 15 RPM.
(1) If the performance of all cylinders are within f15 RPM proceed to Step lb and validate conclusions in the manual (enhanced) mode.
(2) If the cylinders are not within +/- 15 RPM proceed to Step 2.
b. Select the manual injector balance test screen and evaluate each cylinders' performance to specification +/- 15 RPM. If the performance of all cylinders are within +/- 15 RPM continue to diagnose the concern per standard diagnostic procedures and methods. If the cylinders are not within +/- 15 RPM proceed to Step 2.
NOTE
BOTH OF THE ABOVE TESTS SHOULD BE USED TOGETHER TO DETERMINE IF AN INJECTOR(S) IS FOUND FAULTY AND REQUIRES REPLACEMENT.
NOTE
THE DIFFICULTY IN PRESENTING A CLEAR REPRESENTATION OF CYLINDER PERFORMANCE AT ACTUAL OFF-IDLE ENGINE SPEEDS MAY RESULT IN INACCURATE EVALUATION. THE SERVICE PROCEDURE STATED BELOW INDICATES MAXIMIZING THE FUEL RAIL PRESSURE (FRP) IN ORDER TO SIMULATE AN OFF-IDLE AND/OR UNDER LOAD CONDITION, YET PROVIDES A RELIABLE DEPICTION OF THE CYLINDER PERFORMANCE. CUSTOMER CONCERNS THAT ARE CLAIMED TO BE EXPERIENCED AT OFF-IDLE ENGINE SPEEDS OR UNDER LOAD CONDITIONS SHOULD BE ADDRESSED USING THIS SERVICE PROCEDURE.
2. With KOER at idle engine speed use the IDS (or equivalent scan tool) and proceed to the PID selection screen in the DataLogger menu.
a. Select the FRP_DSD # (Fuel Rail Pressure Desired) PID and manually increase the pressure between 15000-16000 psi (105-113 kPa).
b. Return to the main power balance screen and evaluate each cylinders' performance to specification +/- 15 RPM.
c. Select the manual injector balance test screen and evaluate each cylinders' performance to specification +/- 15 RPM expected normal Off-Idle power balance representation.
NOTE
THE VERBIAGE "EXPECTED NORMAL" AS STATED ABOVE IMPLIES WHEN A POWER BALANCE TEST EXHIBITS MEASUREMENTS AS SHOWN, SHOULD NOT RESULT IN AN IMMEDIATE ASSUMPTION OF FAILED INJECTOR(S)/CYLINDER CONTRIBUTION, FOLLOW THE SERVICE PROCEDURE AS OUTLINED ABOVE TO ACCURATELY ASSESS THE CONCERN. (Figure 1)
WARRANTY STATUS: Eligible Under Provisions Of New Vehicle Limited Warranty Coverage And Emissions Warranty Coverage
IMPORTANT: Warranty coverage limits/policies are not altered by a TSB. Warranty coverage limits are determined by the identified causal part.
OPERATION DESCRIPTION TIME
MT081607 Use SLTS Operations If Actual
Available; Claim Additional Time
Diagnosis Or Labor
Performed As Actual Time.
DEALER CODING
CONDITION
BASIC PART NO. CODE
12A650 04
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