ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines - ISC, ISCe, QSC8.3, ISL, ISLe3, ISLe4 and QSL9 Engines - Troubleshooting and Repair Manual

Engine Performance Troubleshooting Tree – CM554 Electronic Control System with CAPS Fuel System

Symptoms

Engine Acceleration or Response Poor
Cranking Fuel Pressure is Low
Engine Operating Fuel Pressure is Low
Engine Decelerates Slowly
Engine Difficult to Start or Will Not Start (Exhaust Smoke)
Engine Difficult to Start or Will Not Start (No Exhaust Smoke)
Engine Power Output Low
Engine Runs Rough at Idle
Engine Runs Rough or Misfires
Engine Speed Surges at Low or High Idle
Engine Speed Surges Under Load or in Operating Range
Smoke, Black – Excessive
Smoke, White – Excessive
Engine Shuts Off or Dies Unexpectedly or Dies During Deceleration
Engine Starts But Will Not Keep Running
Engine Will Not Reach Rated Speed (RPM)
Intake Manifold Pressure (Boost) is Below Normal

How To Use This Tree

This symptom tree can be used to troubleshoot all of the performance-based symptoms listed above. Start by performing Step 1 troubleshooting. Step 2 will ask a series of questions and will provide a list of troubleshooting steps to perform, depending on the symptom. Perform the list of troubleshooting in the sequence shown in the Specifications/Repair section of the tree.

Shop Talk

Driveability is a term that in general describes vehicle performance on the road. Driveability problems for an engine can be caused by several different factors. Some of the factors are engine-related and some are
not. Before troubleshooting, it is important to determine the exact complaint and whether the engine has a real driveability problem or if it simply does
not meet driver expectations.

Low power is a term that is used in the field to describe many different performance problems. Low power is defined as the inability of the engine to produce the power necessary to move the vehicle at a speed that can be reasonably expected under the given conditions of load, grade, wind, and so on.

Poor acceleration or response is described as the inability of the vehicle to accelerate satisfactorily from a stop or from the bottom of a grade. It can also be the lag in acceleration during an attempt to pass or overtake another vehicle at conditions less than rated speed and load. Poor acceleration or response is difficult to troubleshoot because it can be caused by several factors.

Troubleshooting Steps

STEPS		SPECIFICATIONS
STEP 1.	Perform basic troubleshooting procedures.
	STEP 1A. Check for active fault codes or high counts of inactive fault codes.	Active fault codes or high counts of inactive fault codes?
	STEP 1B. Perform basic troubleshooting checks.	All steps have been verified to be correct?
STEP 2.	Determination of engine symptom.
	STEP 2A. Low power, poor acceleration, or poor response.	Is the engine symptom low power, poor acceleration, or poor response?
	STEP 2B. Engine misfire, engine speed surge, or engine speed unstable.	Is the engine symptom engine misfire, engine speed surge, or engine speed unstable?
	STEP 2C. Excessive white or black smoke.	Is the engine symptom excessive white or black smoke?
	STEP 2D. Low intake manifold pressure.	Is the engine symptom low boost pressure?
	STEP 2E. Engine will not start or difficult to start, or engine shuts off unexpectedly.	Is the symptom engine will not start or difficult to start, or engine shuts off unexpectedly?
STEP 3.	No-start troubleshooting procedures.
	STEP 3A. Check the ECM keyswitch voltage.	Is the keyswitch voltage equal to battery voltage?
	STEP 3B. Check the ECM battery supply voltage.	Is the ECM battery supply voltage equal to the battery voltage?
	STEP 3C. Verify the operation of cold weather starting aids.	If equipped, are cold weather starting aids operating correctly?
	STEP 3D. Check the fuel lift pump pressure.	Is the fuel lift pump pressure greater than the specifications outlined in Procedure 005-045 (Fuel Lift Pump) in the ISC, ISCe, QSC8.3, ISL and QSL9 Engines Troubleshooting and Repair Manual, Bulletin 4021418?
	STEP 3E. Verify fuel pressure sensor accuracy.	Is the accumulator pressure value less than 34.5 bar [500 psi]?
	STEP 3F. Check the accumulator pressure.	Is accumulator pressure greater than 293 bar [4250 psi] while cranking?
	STEP 3G. Use INSITE™ electronic service tool to check the CPS crank state.	Does CPS state read Valid Sync while cranking?
	STEP 3G-1. Check and adjust speed/position sensor air gap.
	STEP 3H. Measure gear pump pressure.	Is the fuel gear pump pressure greater than the specifications outlined in Procedure 005-089 (Fuel Pump Gear Pump Module) in the ISC, ISCe, QSC8.3, ISL and QSL9 Engines Troubleshooting and Repair Manual, Bulletin 4021418?
	STEP 3I. Perform the injection control valve (IVC) click test.	Does the injection control valve pass the click test?
	STEP 3J. Perform the pumping control valve (PCV) click test.	Do the pumping control valves pass the click test?
	STEP 3K. Check the distributor rotor timing.	Distributor rotor timing is correct as outlined in Procedure 005-072 (Rotor, CAPS Fuel Injection Pump) in the ISC, ISCe, QSC8.3, ISL and QSL9 Engines Troubleshooting and Repair Manual, Bulletin 4021418?
	STEP 3L. Inspect the gear pump coupling for wear.	Is the gear pump drive shaft or coupling worn?
STEP 4.	Fuel system troubleshooting procedures.
	STEP 4A. Check for fault codes.	Are fuel system fault codes active?
	STEP 4B. Check the CAPS fuel pump wiring.	All fuel pump wiring is undamaged and is properly connected?
	STEP 4C. Check transorb diode.	Does the rough running, black smoke, or surge complaint continue?
	STEP 4D. Check for air in the high-pressure pump fuel supply.	Is air present in the fuel supply?
	STEP 4E. Measure the fuel inlet restriction.	Is the fuel inlet restriction less than the specifications outlined in Procedure 006-020 (Fuel Inlet Restriction) in the ISC, ISCe, QSC8.3, ISL and QSL9 Engines Troubleshooting and Repair Manual, Bulletin 4021418?
	STEP 4F. Measure the fuel gear pump pressure.	Is the fuel gear pump pressure greater than the specifications outlined in Procedure 005-089 (Fuel Pump Gear Pump Module) in the ISC, ISCe, QSC8.3, ISL and QSL9 Engines Troubleshooting and Repair Manual, Bulletin 4021418?
	STEP 4G. Perform the injection control valve click test.	Does the injection control valve pass the click test?
	STEP 4H. Perform the pumping control valve click test.	Do the pumping control valves pass the click test?
	STEP 4I. Measure fuel drain line restriction.	Is the drain line restriction less than specification?
	STEP 4J. Perform the single cylinder cutout test.	Can the miss or excessive smoke be attributed to a single cylinder?
	STEP 4K. Verify the fuel temperature sensor is within specification.	Is the fuel temperature sensor within specification?
	STEP 4L. Check for excessive injector drain leakage.	Are only a few drops of fuel per minute draining from the back of the cylinder head?
	STEP 4M. Pop test the injectors.	The injector spray pattern is correct and the injectors pop between 275 and 300 bar [3989 and 4351 psi]?
	STEP 4N. Inspect the gear pump coupling for wear.	Is the gear pump drive shaft or coupling worn?
STEP 5.	Air handling troubleshooting procedures.
	STEP 5A. Inspect the turbocharger blades for damage.	Damage found on turbocharger blades?
	STEP 5B. Check the turbocharger axial and radial clearances.	Are the turbocharger axial and radial bearing clearances within specification?
	STEP 5C. Inspect the wastegate actuator rod for travel.	Does the wastegate actuator rod move?
	STEP 5C-1. Inspect the wastegate actuator rod for travel.
STEP 6.	Electronic feature troubleshooting procedures.
	STEP 6A. Verify throttle pedal travel.	Does the throttle position read zero when the throttle is released and 100 percent when the throttle is depressed?
	STEP 6B. Check ambient air pressure sensor accuracy (if equipped).	Is the reading within 50.8 mm-Hg [2 in-Hg] of local barometric pressure?
	STEP 6C. Check intake manifold pressure sensor accuracy.	Is the intake manifold pressure reading less than 102 mm-Hg [4 in-Hg]?
	STEP 6D. Verify electronic feature settings are correct.	Are the electronic features set correctly?
STEP 7.	Base engine troubleshooting procedures.
	STEP 7A. Verify overhead adjustments are correct.	Are the overhead settings within the reset limits?
	STEP 7B. Verify engine brake adjustment (if equipped).	Are the engine brake settings within the reset limits?
	STEP 7C. Inspect the charge air cooler.	Is the charge air cooler free of cracks, holes, or other damage?
	STEP 7D. Check air intake restriction.	Is air intake restriction greater than 635 mm-H 2O [25 in-H 2O]?
	STEP 7E. Check exhaust restriction.	Is exhaust back pressure less than 72 mm-Hg [3 in-Hg]?
	STEP 7F. Check engine blowby.	Are the engine blowby measurements within specification?
	STEP 7F-1. Verify turbocharger contribution to engine blowby.

Guided Step 1 – Perform basic troubleshooting procedures.

Guided Step 1A – Check for active fault codes or high counts of inactive fault codes.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Check for active fault codes. Use INSITE™ electronic service tool to read the fault codes.
Active fault codes or high counts of inactive fault codes?
YES	NO
No Repair	No Repair
Go to appropriate fault code troubleshooting tree	Go to 1B

Guided Step 1B – Perform basic troubleshooting checks.
Action The following items must be checked or verified before continuing: Verify the fuel level in the tanks, regardless of what the gauge reads. Verify there have not been any changes to CPL components on the engine. Verify fuel grade is correct for the application. Verify the engine is operating within the recommended altitude. Verify engine oil is at the correct level. Verify engine parasitics have not changed. Verify engine duty cycle has not changed. Verify engine cranking speed is greater than 150 rpm. Verify battery voltage is adequate.
All steps have been verified to be correct?
YES	NO
No Repair	Correct the condition and verify complaint is no longer present after repair.
Go to 2A	Repair complete

Guided Step 2 – Determination of engine symptom.

Guided Step 2A – Low power, poor acceleration, or poor response.
Action Interview the driver and verify the complaint.
Is the engine symptom low power, poor acceleration, or poor response?
YES	NO
Perform the troubleshooting steps in the recommended order listed below: Step 4 – Fuel System Checks Step 5 – Air Handling Checks Step 6 – Electronics Checks Step 7 – Base Engine Checks.	No Repair
Perform the troubleshooting steps suggested in the repair procedure	Go to 2B

Guided Step 2B – Engine misfire, engine speed surge, or engine speed unstable.
Action Interview the driver and verify the complaint.
Is the engine symptom engine misfire, engine speed surge, or engine speed unstable?
YES	NO
Perform the troubleshooting steps in the recommended order listed below: Step 4 – Fuel System Checks Step 5 – Air Handling Checks Step 6 – Electronics Checks Step 7 – Base Engine Checks.	No Repair
Perform the troubleshooting steps suggested in the repair procedure.	Go to 2C

Guided Step 2C – Excessive white or black smoke.
Action Interview the driver and verify the complaint.
Is the engine symptom excessive white or black smoke?
YES	NO
Perform the troubleshooting steps in the recommended order listed below: Step 5 – Air Handling Checks Step 4 – Fuel System Checks Step 7 – Base Engine Checks.	No Repair
Perform the troubleshooting steps suggested in the repair procedure	Go to 2D

Guided Step 2D – Low intake manifold pressure.
Action Interview the driver and verify the complaint.
Is the engine symptom low boost pressure?
YES	NO
Perform the troubleshooting steps in the recommended order listed below: Step 5 – Air Handling Checks Step 4 – Fuel System Checks Step 7 – Base Engine Checks.	No Repair
Perform the troubleshooting steps suggested in the repair procedure	Go to 2E

Guided Step 2E – Engine will not start or difficult to start, or engine shuts off unexpectedly.
Action Interview the driver and verify the complaint.
Is the symptom engine will not start or difficult to start, or engine shuts off unexpectedly?
YES	NO
Perform the troubleshooting steps in the recommended order listed below: Step 3 – No Start Checks Step 4 – Fuel System Checks Step 7 – Base Engine Checks Step 5 – Air Handling Checks Step 6 – Electronics Checks.	No Repair
Perform the troubleshooting steps suggested in the repair procedure	Return to correct symptom tree

Guided Step 3 – No-start troubleshooting procedures.

Guided Step 3A – Check the ECM keyswitch voltage.
Conditions Disconnect the OEM harness from the ECM. Turn keyswitch ON. Action Measure the signal voltage from the keyswitch input SIGNAL wire of the OEM harness to the engine block ground. Measure the keyswitch voltage with the keyswitch in the ON position and also with the keyswitch in the START position. Refer to the wiring diagram for connector pin identification.
Is the keyswitch voltage equal to battery voltage?
YES	NO
No Repair	Repair or replace the OEM power harness or keyswitch, or check the battery connections.
Go to 3B	Repair complete

Guided Step 3B – Check the ECM battery supply voltage.
Conditions Turn keyswitch OFF. Disconnect the ECM power harness from the ECM. Action Measure the voltage from the ECM battery supply (+) to the ECM battery supply (-) pins in the OEM harness connector. Refer to the wiring diagram for connector pin identification.
Is the ECM battery supply voltage equal to the battery voltage?
YES	NO
No Repair	Repair or replace the ECM power harness. Check the battery connections and fuse terminals.
Go to 3C	Repair complete

Guided Step 3C – Verify the operation of cold weather starting aids.
Action Make sure the intake air heater and other cold starting aids are operational, if equipped. Refer to Procedure 008-011 (Coolant Heater) in Section 8, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Refer to Procedure 010-029 (Cold Starting Aid) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
If equipped, are cold weather starting aids operating correctly?
YES	NO
No Repair	Repair cold weather starting aids. Refer to Procedure 010-029 (Cold Starting Aid) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 3D	Repair complete

Guided Step 3D – Check the fuel lift pump pressure.
Conditions Refer to Procedure 005-045 (Fuel Lift Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Measure the fuel lift pump output pressure. Refer to Procedure 005-045 (Fuel Lift Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. At initial key-on, the lift pump will run for 30 seconds, then it will stop. Lift pump pressure can be low if fuel prime was lost. Multiple keyswitch cycles can be necessary to prime the fuel system using the electric lift pump.
Is the fuel lift pump pressure greater than the specifications outlined in Procedure 005-045 (Fuel Lift Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418?
YES	NO
No Repair	Find and repair the cause of low lift pump pressure. Refer to Procedure 005-045 (Fuel Lift Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 3E	Repair complete

Guided Step 3E – Verify fuel pressure sensor accuracy.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Use INSITE™ electronic service tool to monitor accumulator pressure. The engine speed must be zero for at least 1 minute before performing this test.
Is the accumulator pressure value less than 34.5 bar [500 psi]?
YES	NO
No Repair	Replace the fuel pressure sensor. Refer to Service Bulletin, CAPS Fuel Pressure Sensor Kit, 4021293 or 4021294.
Go to 3F	Repair complete

Guided Step 3F – Check the accumulator pressure.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Use INSITE™ electronic service tool to read accumulator pressure while cranking the engine.
Is accumulator pressure greater than 293 bar [4250 psi] while cranking?
YES	NO
No Repair	No Repair
Go to 3L	Go to 3G

Guided Step 3G – Use INSITE™ electronic service tool to check the CPS crank state.
Conditions Connect INSITE™ electronic service tool. Turn keyswitch ON. Action Use INSITE™ electronic service tool to monitor CPS state while cranking the engine.
Does CPS state read Valid Sync while cranking?
YES	NO
No Repair	Troubleshoot the engine speed sensor circuit. See Fault Codes 115 and 121.
Go to 3H	Go to 3G-1

Guided Step 3G-1 – Check and adjust the speed/position sensor air gap.
Conditions Install the sensors. Action Check and adjust the speed/position sensor air gap. Check the air gap between the ESS/EPS and the camshaft ring gear. Since the EPS and ESS are mounted on the same boss, the air gap can be measured using the outside sensor bore. This measurement can usually be taken without removing the air compressor. Bar the engine over 2 full revolutions ( clockwise facing the front of the engine). Use a depth micrometer and measure the distance from the face of the gear housing boss to the face of the camshaft ring gear. Record this measurement “A”. Measure the gap in 45 degree camshaft rotation increments. If the measurements “A” varies by more than 0.051 mm [0.002 in] the tone wheel is warped, or the camshaft gear is walking. Next measure the sensor. Use a depth micrometer to measure the distance from the bottom of the sensor mounting flange to the tip of the threaded end of the sensor. Record this as measurement “B”. The air gap can be calculated by subtracting B from A (air gap measurement equals A minus B). If the air gap is less than 0.406 mm [0.016 in] add a 0.508 mm [0.020 in] shim to sensor. Minimum Air Gap: 0.406 mm [0.016 in] Maximum Air Gap: 1.020 mm [0.040 in]
Are the sensor(s) depth measurements within specification?
YES	NO
No Repair.	Replace the engine speed/position sensor(s). Refer to Procedure 019-042 (Engine Speed Sensor (ESS)) in Section 19, ISC, QSC8.3, and ISL Electronic Control System, Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 3H	Repair Complete

Guided Step 3H – Measure gear pump pressure.
Conditions Connect a fuel pressure gauge to the Compuchek™ fitting on the cam housing. Action Measure the gear pump pressure while cranking the engine. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is the fuel gear pump pressure greater than the specifications outlined in Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418?
YES	NO
No Repair	No Repair
Go to 3I	Go to 3K

Guided Step 3I – Perform the injection control valve (ICV) click test.
Conditions Connect INSITE™ electronic service tool. Turn keyswitch ON. Action Use INSITE™ electronic service tool to perform the ICV click test. Refer to Procedure 005-078 (Injection Control Valve) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Does the injection control valve pass the click test?
YES	NO
No Repair	Replace the injection control valve stator. Refer to Procedure 019-430 (Injection Control Valve Stator) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 3J	Repair complete

Guided Step 3J – Perform the pumping control valve (PCV) click test.
Conditions Connect INSITE™ electronic service tool. Turn keyswitch ON. Action Use INSITE™ electronic service tool to perform the front and rear PCV test. Refer to Procedure 005-079 (Pumping Control Valve) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Do the pumping control valves pass the click test?
YES	NO
Replace the injection control valve module. Refer to Procedure 005-086 (Fuel Pump Distributor and Injection Control Valve Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	Replace the accumulator module. Refer to Procedure 005-085 (Fuel Pump Accumulator Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Repair complete	Repair complete

Guided Step 3K – Check the distributor rotor timing.
Conditions Turn keyswitch OFF. Action Inspect the distributor rotor timing and check for a seized rotor. Refer to Procedure 005-072 (Rotor, CAPS Fuel Injection Pump (Rotor, CAPS Fuel Injection Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Distributor rotor timing is correct as outlined in Procedure 005-072 (Rotor, CAPS Fuel Injection Pump Rotor, CAPS Fuel Injection Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418?
YES	NO
No Repair	Replace the fuel injection pump. Refer to 005-229 (Fuel Injection Pump) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 3L	Repair complete

Guided Step 3L – Inspect the gear pump coupling for wear.
Conditions Turn keyswitch OFF. Remove the gear pump module. Action Inspect the gear pump drive shaft coupling and shaft for wear. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5 in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is the gear pump drive shaft or coupling worn?
YES	NO
Replace the gear pump module. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	Replace the injection control valve. Refer to Procedure 005-086 (Fuel Pump Distributor and Injection Control Valve Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Repair complete	Repair complete

Guided Step 4 – Fuel system troubleshooting procedures.

Guided Step 4A – Check for fault codes.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Use INSITE™ electronic service tool to read the fault code information. Check for active fuel system fault codes related to the complaint.
Are fuel system fault codes active?
YES	NO
Follow the appropriate troubleshooting tree.	No Repair
Repair complete	Go to 4B

Guided Step 4B – Check the CAPS fuel pump wiring.
Action Check the injection control valve, pressure control valve, fuel pressure sensor, and fuel temperature sensor wiring for damage, cuts, and loose connections.
All fuel pump wiring is undamaged and is properly connected?
YES	NO
No Repair	Replace the malfunctioning fuel system component.
Go to 4C	Repair complete

Guided Step 4C – Check the transorb diode.
Conditions Unplug the fuel pressure sensor. Action Unplug the fuel pressure sensor.
Does the rough running, black smoke, or surge complaint continue?
YES	NO
No Repair	Replace the transorb diode. Refer to Procedure 019-184 (Transient Suppressor) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 4D	Repair complete

Guided Step 4D – Check for air in the high-pressure pump fuel supply.
Conditions Refer to Procedure 006-003 (Air in Fuel) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Check for air in the fuel. Refer to Procedure 006-003 (Air in Fuel) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is air present in the fuel supply?
YES	NO
Locate and correct the cause of air ingestion in the fuel supply system. Sources of air ingestion include loose fuel filters, loose fuel line fittings, loose or cracked fuel tank stand-pipes, and severe restrictions in the fuel supply lines and filters.	No Repair
Repair complete	Go to 4E

Guided Step 4E – Measure the fuel inlet restriction.
Conditions Perform this check during the complaint. Action Measure the fuel inlet restriction. Refer to Procedure 006-020 (Fuel Inlet Restriction) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is the fuel inlet restriction less than the specifications outlined in Procedure 006-020 (Fuel Inlet Restriction) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418?
YES	NO
No Repair	Locate the cause of the high inlet restriction. Check the OEM fuel inlet plumbing, fuel filters, and lift pump check valve.
Go to 4F	Repair complete

Guided Step 4F – Measure the fuel gear pump pressure.
Conditions Connect a fuel pressure gauge to the Compuchek™ fitting on the cam housing. Action Measure the gear pump pressure while the engine is at the rated condition. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is the fuel gear pump pressure greater than the specifications outlined in Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418?
YES	NO
No Repair	Replace the fuel gear pump module. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 4G	Repair complete

Guided Step 4G – Perform the injection control valve (ICV) click test.
Conditions Connect INSITE™ electronic service tool. Turn keyswitch ON. Action Use INSITE™ electronic service tool to perform the ICV click test. Refer to Procedure 005-078 (Injection Control Valve) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Does the injection control valve pass the click test?
YES	NO
No Repair	Replace the injection control valve stator. Refer to Procedure 019-430 (Injection Control Valve Stator) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 4H	Repair complete

Guided Step 4H – Perform the pumping control valve (PCV) click test.
Conditions Connect INSITE™ electronic service tool. Turn keyswitch ON. Action Use INSITE™ electronic service tool to perform the front and rear PCV click test. Refer to Procedure 005-079 (Pumping Control Valve) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Do the pumping control valves pass the click test?
YES	NO
No Repair	Replace the accumulator module. Refer to Procedure 005-085 (Fuel Pump Accumulator Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 4I	Repair complete

Guided Step 4I – Measure fuel drain line restriction.
Conditions Refer to Procedure 006-012 (Fuel Drain Line Restriction) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Perform this check during the complaint. Action Check the fuel drain line restriction. Refer to Procedure 006-012 (Fuel Drain Line Restriction) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Is the drain line restriction less than specification?
YES	NO
No Repair	Look for causes of high drain line restriction, such as kinked or blocked fuel lines.
Go to 4J	Repair complete

Guided Step 4J – Perform the single cylinder cutout test.
Conditions Turn keyswitch ON. Engine running at low idle. Connect INSITE™ electronic service tool. Action Operate the engine at loaded conditions. Use INSITE™ electronic service tool to perform the single cylinder cutout test to disable individual injectors.
Can the miss or excessive smoke be attributed to a single cylinder?
YES	NO
Replace the fuel injector in the cylinder that was identified using the single cylinder cutout test. Refer to Procedure 006-026 (Injector) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	No Repair
Repair complete	Go to 4K

Guided Step 4K – Verify the fuel temperature sensor is within specification.
Conditions Turn keyswitch to the OFF position. Disconnect the engine harness from the fuel temperature sensor. Install the fuel pressure/temperature sensor breakout cable, Part Number 3162982. Action Check the resistance of the fuel temperature sensor. Measure the resistance from pin B to pin D of the fuel temperature sensor. Refer to Procedure 019-119 (Engine Fuel Temperature Sensor) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Is the fuel temperature sensor within specification?
YES	NO
No Repair	Replace the fuel temperature sensor. Refer to Procedure 019-119 (Engine Fuel Temperature Sensor) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 4L	Repair complete.

Guided Step 4L – Check for excessive injector drain leakage.
Conditions Remove the fuel injector drain banjo fitting from the back of the cylinder head. Action Run the engine at low idle while monitoring the amount of fuel draining from the back of the cylinder head.
Are only a few drops of fuel per minute draining from the back of the cylinder head?
YES	NO
No Repair	A damaged connection between the high-pressure connector and an injector has been detected. Remove all high-pressure connectors and check for burrs or deformation around the tip of the injector. Refer to Procedure 006-052 (Fuel Connector (Head Mounted)) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 4M	Repair complete

Guided Step 4M – Pop test the injectors.
Conditions Remove the injectors. Refer to Procedure 006-026 (Injector) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Pop test the injectors and check for proper spray pattern. Refer to Procedure 006-026 (Injector) in Section 6, the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
The injector spray pattern is correct and the injectors pop between 275 and 300 bar [3989 and 4351 psi]?
YES	NO
No Repair	Replace the malfunctioning injector. Refer to Procedure 006-026 (Injector) in Section 6, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 4N	Repair complete

Guided Step 4N – Inspect the gear pump coupling for wear.
Conditions Turn keyswitch OFF. Remove the gear pump module. Action Inspect the gear pump drive shaft coupling and shaft for wear.
Is the gear pump drive shaft or coupling worn?
YES	NO
Replace the gear pump module. Refer to Procedure 005-089 (Fuel Pump Gear Pump Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	Replace the injection control valve. Refer to Procedure 005-086 (Fuel Pump Distributor and Injection Control Valve Module) in Section 5, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Repair complete	Repair complete

Guided Step 5 – Air handling troubleshooting procedures.

Guided Step 5A – Inspect the turbocharger blades for damage.
Conditions Turn keyswitch OFF. Remove the intake and exhaust pipes from the turbocharger. Action Inspect the compressor and turbine blades for damage or wear. Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Damage found on turbocharger blades?
YES	NO
Replace the turbocharger assembly. Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	No Repair
Repair complete	Go to 5B

Guided Step 5B – Check the turbocharger axial and radial clearance.
Conditions Turn keyswitch OFF. Action Check the turbocharger for correct axial and radial clearance. Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Are the turbocharger axial and radial bearing clearances within specification?
YES	NO
No Repair	Replace the turbocharger. Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 5C	Repair complete

Guided Step 5C – Inspect the wastegate actuator rod for travel.

Conditions

Turn keyswitch OFF.
Remove the integral boost line from the wastegate actuator.

Action

Apply a regulated air supply of 138 kPa [20 psi] to the actuator and check for actuator movement.

SMALL | MEDIUM | LARGE

Does the wastegate actuator rod move?

YES

No Repair

Repair complete

Go to 5C-1

Guided Step 5C-1 – Inspect the wastegate actuator rod for travel.

Conditions

Turn keyswitch OFF.
Remove the e-clip from the wastegate pin and disconnect the actuator rod.

Action

Apply a regulated air supply of 138 kPa [20 psi] to the actuator and check for actuator movement.

SMALL | MEDIUM | LARGE

Does the wastegate actuator rod move?

YES

Move the wastegate lever on the turbocharger back and forth to check for smooth operation. Replace the turbocharger assembly if the wastegate is seized.

Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

Replace the wastegate actuator.

Refer to Procedure 010-050 (Turbocharger Wastegate Actuator) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

Repair complete

Guided Step 6 – Electronic feature troubleshooting procedures.

Guided Step 6A – Verify throttle pedal travel.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Use INSITE™ electronic service tool to monitor the throttle position while fully depressing and releasing the throttle pedal.
Does the throttle position read zero when the throttle is released and 100 percent when the throttle is depressed?
YES	NO
No Repair	Determine and correct the cause of the throttle pedal restriction.
Go to 6B	Repair complete

Guided Step 6B – Check ambient air pressure sensor accuracy (if equipped).
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Start INSITE™ Data Monitor/Logger and compare INSITE™ reading for Barometric Air Pressure to the local barometric pressure using the table below. Refer to Procedure 018-028 (Barometric Pressure at Altitude) in Section V.
Is the reading within 50.8 mm-Hg [2 in-Hg] of local barometric pressure?
YES	NO
No Repair	Replace the barometric pressure sensor. Refer to Procedure 019-004 (Barometric Air Pressure Sensor) in Section 19. in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 6C	Repair Complete

Guided Step 6C – Check intake manifold pressure sensor accuracy.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Start INSITE™ electronic service tool Data/Monitor/Logger and read the value of intake manifold pressure.
Is the intake manifold pressure reading less than 102 mm-Hg [4 in-Hg]?
YES	NO
No Repair	Replace the intake manifold pressure sensor. Refer to Procedure 019-061 (Intake Manifold Pressure Sensor) in Section 19, in the Electronic Control System ISC, QSC8.3, and ISL Troubleshooting and Repair Manual, Bulletin 3666271.
Go to 6D	Repair complete

Guided Step 6D – Verify electronic feature settings are correct.
Conditions Turn keyswitch ON. Connect INSITE™ electronic service tool. Action Use INSITE™ electronic service tool to verify the following adjustable parameters are set correctly: Maximum Vehicle Speed Powertrain Protection Rear Axle Ratio Tailshaft Teeth Tire Revolutions per Mile Gear-Down Protection Cruise Control Droop Settings Cruise Control Maximum Vehicle Speed.
Are the electronic features set correctly?
YES	NO
No Repair	Use INSITE™ electronic service tool to correct programmable features.
Go to 2A	Repair complete

Guided Step 7 – Base engine troubleshooting procedures.

Guided Step 7A – Verify overhead adjustments are correct.
Conditions Turn keyswitch OFF. Remove the rocker lever cover. Refer to Procedure 003-011 (Rocker Lever Cover) in Section 3, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Measure the overhead settings. Refer to Procedure 003-004 (Overhead Set) in Section 3, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Are the overhead settings within the reset limits?
YES	NO
No Repair	Adjust the overhead settings. Refer to Procedure 003-004 (Overhead Set) in Section 3, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 7B	Repair complete

Guided Step 7B – Verify engine brake adjustment (if equipped).
Conditions Turn keyswitch OFF. Remove the rocker lever cover. Refer to Procedure 003-011 (Rocker Lever Cover) in Section 3, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Verify the engine brakes are operating correctly. Measure the engine brake settings. Refer to Procedure 020-004 (Engine Brake Assembly) in Section 20, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Are the engine brake settings within the reset limits?
YES	NO
No Repair	Adjust the engine brake settings. Refer to Procedure 020-004 (Engine Brake Assembly) in Section 20, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Go to 7C	Repair complete

Guided Step 7C – Inspect the charge air cooler.

Conditions

Refer to Procedure 010-027 (Charge-Air Cooler) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

Action

Inspect the charge air cooler for cracks, holes, or other damage.

Refer to Procedure 010-027 (Charge-Air Cooler) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

SMALL | MEDIUM | LARGE

Is the charge air cooler free of cracks, holes, or other damage?

YES

No Repair

Repair the charge air cooler assembly.

Go to 7D

Repair complete

Guided Step 7D – Check air intake restriction.

Conditions

Refer to Procedure 010-031 (Air Intake Restriction) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

Action

Check the intake system restriction by installing a vacuum gauge into the air intake system.

Refer to Procedure 010-031 (Air Intake Restriction) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

SMALL | MEDIUM | LARGE

Is air intake restriction greater than 635 mm-H
₂O [25 in-H
₂O]?

YES

Correct the cause of high intake air restriction.

Check for a plugged air filter or restricted air intake piping.

No Repair

Repair complete

Go to 7E

Guided Step 7E – Check exhaust restriction.

Conditions

Refer to Procedure 011-009 (Exhaust Restriction) in Section 11, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

Action

Check the exhaust system back pressure by installing a pressure gauge into the exhaust system just past the turbocharger outlet.

Refer to Procedure 011-009 (Exhaust Restriction) in Section 11, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.

SMALL | MEDIUM | LARGE

Is exhaust back pressure less than 72 mm-Hg [3 in-Hg]?

YES

No Repair

Inspect the exhaust system for the source of high restriction.

Go to 7F

Repair complete

Guided Step 7F – Check engine blowby.
Conditions Refer to Procedure 014-005 (Engine Testing (Engine Dynamometer)) in Section 14, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418. Action Measure the engine blowby. Refer to Procedure 014-005 (Engine Testing (Engine Dynamometer)) in Section 14, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Are the engine blowby measurements within specification?
YES	NO
No Repair	No Repair
Return to Step 2 or contact a Cummins Inc. service representative for further diagnostic and troubleshooting instructions.	Go to Step 7F-1.

Guided Step 7F-1 – Verify turbocharger contribution to engine blowby.
Conditions Turn keyswitch OFF. Connect the appropriate orifice to the end of the blowby draft tube. Remove the turbocharger oil drain line from the block and drain into a bucket. Start the engine. Action Load engine to rated rpm on a chassis dynamometer. Measure the engine blowby as outlined in Procedure 014-005 (Engine Testing (Engine Dynamometer)) in Section 14, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.
Has the total engine blowby dropped more than 30 percent of the total?
YES	NO
Replace the turbocharger assembly. Refer to Procedure 010-033 (Turbocharger) in Section 10, in the ISC, ISCe, QSC8.3, ISL and QSL9 Troubleshooting and Repair Manual, Bulletin 4021418.	The engine may need to be rebuilt. See the engine rebuild specifications.
Repair complete.	Repair complete.

Last Modified: 24-Sep-2008

Feedback / Help