6.0 Power Stroke Engine Diagnostic & Troubleshooting Guide

Page Contents:

  1. Key Terms & Acronyms
  2. Smoke Signals - Understanding Exhaust Smoke Colors
  3. Diagnostic Trouble Codes (DTC)
  4. Parameter ID's (PID)
  5. No Start, Hard Start, Runs Rough, Stalling Conditions
  6. Low Power & Driveability Concerns
  7. 6.0 Power Stroke Replacement Parts List

The 6.0L Power Stroke features an array of sensors and electrical components that must work in conjunction with one another in order for an engine to run properly. Diagnostic procedures and relevant information, including various sensor KOEO/KOER specs are included below. An scantool or diagnostic software with enhanced functionality is required for many of the operations listed below; a typical code reader will not suffice.

Key Terms & Acronyms




On-board diagnostics system, generation II


Malfunction indicator light (synonymous with CEL in most instances)


Check engine light (synonymous with MIL in most instances)


Diagnostic trouble code


Parameter ID


Powertrain control module


Key ON, engine OFF


Key ON, engine RUNNING

Scantools and/or diagnostic equipment are plugged into the vehicle's 16 pin OBD-II connector in order to retrieve DTCs stored in the PCM. Some, but not all DTCs will cause the MIL (CEL) to illuminate. Parameter ID's are various retrievable sensor readouts that can be viewed in real time with a compatible scantool. They are a technician's greatest asset in identifying the source(s) of engine related faults and performance concerns. Certain diagnostic tests and routines are performed KOEO, while others require KOER conditions.

Smoke Signals | Causes of Blue, White, & Black Smoke

The color of any visible smoke emitted from the tailpipe is a useful indicator in combustion characteristics (or lack thereof). Identifying smoke is particularly useful in hard start, no start, and performance related issues. A lack of smoke is equally beneficial in no start/hard start scenarios.

White Smoke

White smoke is the result of raw, atomized fuel leaving the combustion chamber. Raw fuel is indicative that there is a lack of heat in the combustion chamber and therefore auto-ignition is not occurring. Recall that diesel fuel is ignited by the heat produced from compression. However, glow plugs serve as a starting aid to produce the heat necessary to begin the combustion process when an engine is cold. White smoke during cranking often points to a glow plug system issue; the engine is receiving fuel, but it is not igniting. White smoke while running may indicate a cylinder with low compression or, in certain circumstances, an injector that is stuck open. Note - "white" smoke may also be described as lightly gray in color.

Black Smoke

Black smoke is the result of partially burnt fuel; there is adequate heat for combustion, however the mixture is rich and thus there is a lack of air or abundance of fuel during combustion. If black smoke is present and a low power condition is being experienced, an airflow issue is suspect (low turbocharger boost, intercooler boot leak, plugged air filter, etc).

Gray Smoke

Gray smoke is the result of oil burning in the exhaust system. This is often caused by a turbocharger seal failure on the turbine (exhaust) side, causing engine oil to enter the exhaust system and burn. Under such circumstances, engine oil may drop from the tailpipe; this almost always indicates that a turbocharger replacement/overhaul is necessary.

Blue Smoke

Blue smoke indicates that engine oil is being burned in the combustion chamber. The smoke resembles that emitted by a 2 stroke gasoline engine that is running rich. This typically indicates that there is a leak on the compressor side of the turbocharger via a failed seal.

Harness Chaffing on the 6.0 Power Stroke

Wiring harness chaffing is historically a common occurrence on all 6.0L Power Stroke engines. Do not assume that this is a phenomenon that does not affect your engine. Wire chaffing occurs when the engine wiring harness and loom vibrates against an engine component - a sensor bracket or valve cover, for example - to the point that the loom and wire insulation are ground down and the bare copper wire within is exposed. Although rare, chaffing can occur with the wire loom intact. It is important to inspect areas where the wiring harness comes in contact with a metal component or makes a sharp bend. A quick survey of the wiring harness generally exposes such instances. If you're chasing electrical demons, shorts, or breaks in an electrical circuit, this should be your starting point.

Diagnostic Trouble Codes (DTCs)

DTCs are your greatest asset and worst enemy when it comes to 6.0L Power Stroke diagnostics. In many situations, a DTC may indicate a system that is malfunctioning while the individual sensor that it refers to is not the problem. An injector control pressure low DTC, for example does not necessary mean that the ICP sensor is malfunctioning; although it might be. Another example is the occurrence of P2614 (camshaft position sensor) and P2617 (crankshaft position sensor) being set simultaneously. This is never an issue with the two sensors and almost always set as the result of a long crank, no start condition. The moral of the story is that a comprehensive diagnosis is always required until the underlying problem is identified and verified.

A scantool or diagnostic software with enhanced diagnostic features is ideal when troubleshooting 6.0L Power Stroke engine problems. You need to be able to perform basic and advanced system tests in addition to monitoring the output of various sensors simultaneously. In the information below when we refer to "monitoring" a PID, we're doing so with AutoEnginuity's diagnostic software suite.

Misleading, Erroneous, & Phantom DTCs

P1368 - FICM supply voltage low

Do not attempt to crank or start the engine until battery voltage is verified. This is typically triggered by a dead battery, the source of which may very well be a failed alternator. Charge the vehicle batteries until they measure 12.5 to 12.7 volts. If the batteries will not charge into this range or hold a charge within this range, they need to be replaced. Once good system voltage is verified, start the engine and measure battery voltage (alternator output) after allowing the engine to run for several minutes. Battery voltage KOER should be in excess of 13.5 volts with all lights and accessories active if the alternator is functioning properly.

A FICM can be killed in seconds due to a low voltage condition and they are a relatively expensive to replace. This code does not, however, immediately indicate that the FICM experienced an internal fault.

P2614, P2617 set simultaneously

P2614 and P2617 are camshaft position sensor (CPS) and crankshaft position sensor (CKP) DTCs, respectively. The odds that both sensors fail simultaneously is slim-to-none, especially considering failures of either sensor are not entirely common to the 6.0L Power Stroke. Replacing the CPS is not particularly difficult, however reaching the CKP sensor will take you the better part of a day. These codes are generally triggered by a long or extended crank condition. If you fall under this category, ignore and clear the codes.

P2284 through P2291, injector control pressure codes (ICP)

ICP codes include out of range/performance, circuit low, circuit high, pressure low, pressure high, etc. Don't jump to the conclusion that the ICP sensor is faulty. Further diagnostics, including monitoring of the IPR valve duty cycle, are necessary to identify any DTC related to the high pressure oil system.

P2263 - turbocharger system performance

When turbocharger boost is low for a given condition, this DTC is set; it is generic and does very little to isolate the root problem. The most common issues with a 6.0L Power Stroke that would set this code are 1) VGT solenoid, 2) mechanically stuck VGT vanes in the turbine housing, 3) a blown intercooler boot (truck will have a low power condition), and 4) a failed MAP sensor. MAP sensor failures are not particularly common. Monitor MAP and VGT solenoid duty cycle while manually commanding the VGT vanes to open and close. If MAP does not change and/or there is no audible difference between the VGT open and closed, the vanes are mechanically stuck (extremely common) or the VGT solenoid is bad. If the vanes are changing position properly, continue to troubleshoot.

P0261 through P0280, all fuel injector codes

An injector code does not always indicate that an injector is bad. The issue could be a chaffed harness, faulty FICM, or low injector control pressure. Monitor ICP, IPR valve duty cycle, and FICM function simultaneously while engine is idling. A cylinder contribution/power balance test will also isolate a cylinder with a dead injector. If it is suspected that an injector solenoid is sticking do to stiction, an oil additive such as Archoil 9R100 friction modifier may help free up the injector spool valve.

P0341 - camshaft position sensor

The engine will immediately stall if the CPS sensor loses signal as an injector cannot fire if it doesn't know where the cylinder is with regard to engine timing. If the engine did not stall but this code was set, do not immediately replace the CPS; it may not be the root cause.

P0401, P0402 - EGR flow insufficient or excessive

The EGR valve is likely mechanically stuck in either the open or closed position. EGR valves are expensive, cleaning them is not (a gasket kit is ~ $10). If code returns after cleaning, valve may have electrical issue and should be replaced.

P0471 - EBP sensor range/performance

An exhaust backpressure sensor DTC can be set for a number of reasons. In order to avoid replacing a perfectly functional EBP sensor, clean the EBP tube and see if the DTC returns. If it does, replace the sensor. The tube often becomes clogged with soot and this DTC is set once the sensor reading is found to be out of range for the ensuing conditions. Note - 2003 and early 2004 model year engines do NOT use the EBP sensor. It's there, but the PCM does not use the sensor data for any purpose.

P0603 - Keep alive memory

KAM is short for "keep alive memory", which is essentially information stored by the PCM through its various learning functions - transmission shift points, the VGT position schedule, and EGR schedule, for example. This code will be set anytime the batteries are disconnected for a period of time. The systems will all relearn perpetually and this should not be a concern. Transmission shift points and turbocharger performance may seem lackluster until these systems re-map themselves.

6.0 Power Stroke Diagnostic Parameter (PID) Specs & Ranges


KOEO Spec/Range

Engine Cranking Spec/Range

KOER Spec/Range

ICP sensor pressure

0 psi

500 psi min to start engine

650 - 800 psi @ idle

ICP sensor voltage


0.80 volts min


IPR valve duty cycle

~14 - 15%

~ 84% until ICP rises

30% max @ idle
(22 - 28% normal)

Engine RPM


~ 200 rpm

650 - 750 rpm @ idle

FICM main power

45 - 48 volts

45 - 48 volts

45 - 48 volts

FICM logic power

11 - 12 volts

11 - 12 volts

nominal 12 volts

FICM vehicle power

11 - 12 volts

11 - 12 volts

nominal 12 volts

Manifold absolute pressure (MAP)

~ 14.7 (sea level) - 11.3 (7,000 ft) psi



Manifold gauge pressure (MGP)

0 psi


0 - 28 psi
(22 psi min @ full load, 3,300 rpm)

Barometric pressure

~ 14.7 (sea level) - 11.3 (7,000 ft) psi



Glow plug duty cycle (preheat + post cycle)

0 - 120 seconds



Glow plug resistance

0.5 - 2.0 Ω (KEY OFF)



Glow plug current draw (preheat cycle)

10 - 12 amps per glow plug
(40 - 48 amps per bank)



Fuel pressure

> 45 psi all conditions including full load (45 - 55 psi typical)

EGR valve duty cycle closed position




EGR valve voltage closed position

0.6 - 1.2 volts



EGR valve duty cycle open position

90 - 100%



EGR valve voltage open position

4.0 - 4.52 volts



6.0 Power Stroke No Start, Hard Start, Runs Rough, & Engine Stalling

Preliminary Inspections


Verify Battery Voltage

Low battery voltage can cause a slow crank condition and/or may contribute to FICM failure. Approximately 180 - 200 rpm cranking speed is required to start an engine. Battery voltage should measure 12.5 - 12.7 volts for a fully charged battery in good condition. If battery voltage is within this range but engine cranks slowly or intermittently, suspect corroded/loose connections and/or faulty starter.

Verify Engine Oil Level & Condition

The 6.0L Power Stroke relies on a high pressure oil circuit to build fuel pressure. An engine will stall and a no start condition may occur if the engine oil level is low as it starves the high pressure system. A lack of oil pressure results in limited, impeded, or no injector activity.

Verify Fuel Pressure & Quality

A port on the fuel filter housing is used to measure fuel pressure. A schrader valve fitting is required to adapt most common fuel pressure gages to the port. 45 psi minimum should be observed KOEO, while cranking, and KOER. Any reading below 45 psi indicates a plugged fuel filter, fuel system leak, clogged sending unit (in tank), or faulty lift pump. Examine the fuel in the filter housing for quality. Cloudy fuel is a sign of severe water contamination. Sticky (not slick or slippery) fuel is indicative of spoiled biodiesel, which clogs fuel filters rapidly.

Verify Glow Plug System is Operable

While a glow plug control module (GPCM) fault will typically set a DTC, other glow plug system malfunctions may not (in a perfect world, they SHOULD as the primary purpose of the GPCM is to provide diagnostic functions). Individual glow plug condition can be tested by measuring the resistance between each individual glow plug circuit at the GPCM and the negative battery cable. If white smoke is present while cranking, a glow plug system issue is likely (fuel is being injected into the cylinders accordingly but there is a lack of heat necessary for combustion to occur). If no smoke is present while cranking, the glow plug system is unlikely the cause of a no start/hard start condition.

Glow plug cycle time is determined by engine oil temperature (EOT) and barometric pressure. If the glow plugs do not cycle, verify the readings of these sensors (barometric pressure is equal to atmospheric pressure, EOT should read close to ambient temperature when engine is cold).

PID Monitoring & Diagnostic Tests

Verify ICP & IPR Valve Function

A minimum 500 psi injector control pressure is necessary to start the 6.0L Power Stroke diesel. If oil pressure does not reach or drops below 500 psi an injector will not fire. ICP typically reaches anywhere between 800 and 2,000 psi while cranking. If ICP sensor reading is low, erratic, rises slowly while cranking, or there is another reason to suspect it is bad unplug the sensor and attempt to start the engine (ICP defaults to 750 psi when sensor is unplugged). If engine starts, ICP sensor must be replaced.

The IPR duty cycle relates to the position of the IPR valve. At 15% duty cycle, the IPR valve is fully open. At 85% duty cycle, the IPR valve is fully closed. In the closed position oil pressure is increased and in the open position oil pressure is reduced (HPOP pressure bled off into the crankcase). Monitor ICP actual, ICP desired, and IPR valve duty cycle simultaneously. While cranking engine, IPR duty cycle should start at approximately 85% and slowly decrease during a long crank condition once ICP climbs. An IPR valve defaults to 15% if it is unplugged or has failed. In this instance, an engine will not start as it will not be able to build oil pressure; a low ICP condition should be present. IPR valve duty cycle should not exceed 30% at idle once the engine reaches operating temperature. If it does, suspect a leak in the high pressure oil circuit.

ICP actual will tend to trail ICP desired (what the PCM is commanding) while cranking, but the two should generally be close. If ICP desired is significantly higher than ICP actual the IPR valve may not be functioning correctly and is allowing oil pressure in the high pressure circuit to bleed off. A high pressure system leak (failed o-ring, for example) or bad high pressure oil pump (HPOP) can also cause a low ICP condition. Always verify IPR function before assuming high pressure oil system leak or HPOP failure. A high pressure oil system bleed down test is typically necessary to locate leaks. The test requires a special fitting that allows the system to be pressurized with air while the IPR valve is remotely commanded closed; leaks are then audibly traced.

Verify FICM Voltage & Sync

45 to 48 volts is acceptable. Anything lower than 45 and the FICM needs to be replaced. If FICM output voltage is 0, check FICM vehicle power relay (#304, labeled IDM relay in owners manual). Replace FICM relay when replacing FICM regardless of condition. Note - engine may still run if FICM voltage is lower than 45v, but this signifies a failure is highly likely in the near future.

FICM sync should read a "1" bit (1 for yes, 0 for no) while engine is being cranked or running. A "yes" or "1" value for FICM sync indicates that the FICM is receiving CPS/CKP signal from the PCM. If FICM sync returns a "0" or "no" value, CPS/CKP signal is not being transmitted to the FICM. Verify sensor conditions, connectors, and all wiring to the PCM and FICM.

Verify CPS & CKP Status

If a camshaft or crankshaft position sensor loses signal a DTC will be set. A P2614 and P2617 DTC may be set simultaneously during a long crank condition when there is in fact no problem with either signal. CKP sensor failures are rare. CPS failures are more common. The odds that both sensors will fail together is slim-to-none.

Perform an Injector Buzz Test

An injector "buzz" or "click" test is performed to identify a bad injector or injectors by means of an audible test. When an injector buzz test is initiated the engine will sequentially activate each individual injector solenoid, producing buzzing and clicking sounds as the solenoids are energized. All injectors should produce the same characteristic buzz/clicking sound; any injector that sounds different from the rest should be inspected and may require replacement. If no injectors buzz once the test is initiated, retest the FICM.

Perform a Cylinder Contribution Test

A cylinder contribution or power balance test determines how each individual injector contributes to engine rpm following an injection event. A weak injector will not contribute as much as a strong injector and thus engine rpm will decrease after that injector is fired. The FICM automatically adjusts injector pulse width to account for variances between injection event strength. This function must be briefly turned off in order to perform this test. This is achieved by selecting an injector as if you were to turn it off manually via your scantool/diagnostic system. Select any injector, but do not disable it; this will give you roughly 1 minute to initiate the power balance test before the automatic pulse width adjustment function returns. A straight line is desirable in the results of the cylinder contribution test. If rpm drops significantly for one or more injectors, they should be replaced.

Hard Start and/or Stalling Only When the Engine is Cold

Suspect high pressure oil system leak. A leak in the high pressure oil system may allow oil to drain out of the system while the engine sits. Monitor ICP; if ICP is low but finally reaches a normal state after excessive cranking and/or following a series of stall events, the HPOP may be starving for oil until the reservoir is refilled. Perform aforementioned ICP, IPR monitoring tests while engine is running to verify that the system functions within spec once engine is able to warm up.

Engine Stalls and/or Will Not Start When the Engine is Hot

Check FICM voltage with engine at operating temperature. Suspect high pressure oil leak at STC (snap-to-connect) fitting on high pressure oil pump; extremely common.

Powertrain Control Module (PCM) Tests

There is not a suitable nor standardized test for a PCM unless it is completely blank. All other systems should be tested thoroughly before assuming that a PCM is suspect. PCM failures do happen, but are less common than the aforementioned possibilities. The failure rate is much higher on engines with aftermarket tuners/programmers. Thoroughly inspect wiring harness for chaffing before suspecting PCM. If a no start condition occurs immediately following aftermarket tunes being uploaded, the PCM is likely the problem.

6.0 Power Stroke Low Power & Driveability Concerns

Over-Boost Condition, Manifold Absolute Pressure High

A clogged EGR valve where the valve becomes stuck in the closed position can cause an over-boost condition (excessive MAP). Sticking vanes/unison ring in the turbine housing of the turbocharger can also cause an over-boost condition. If MAP is high under light load conditions, VGT vanes are sticking/stuck.

Low Power Condition, Excessive Turbocharger Lag and/or Low Manifold Absolute Pressure

A number of PIDs need to be monitored in order to identify low power and poor turbocharger performance conditions. Causes include a stuck unison ring in the turbine housing, faulty VGT solenoid, exhaust leak, intake leak (pressure side of turbo), faulty EBP sensor, or faulty MAP sensor. The MAP and EBP sensors can be checked with KOEO. They should both read ~ 14.7 psi at sea level.

Excessive or Insufficient EGR Flow, Low Power Condition

An EGR valve stuck in the open position can cause a low performance condition. If an EGR DTC is present, the first step is to remove, clean, and reinstall the EGR valve with new o-rings/gaskets. You can also test the EGR position range by manually commanding it open and close; you will hear the idle sound change when the valve position changes. If the EGR valve fails to respond to manual commands through a scantool, it is mechanically stuck or has electronically failed (less common).

Engine Jerking, Bucking, Low Power Condition

Fuel pressure, oil pressure, and injector condition can cause such symptoms. Start by testing fuel pressure under load, followed by verifying ICP/IPR function. If these systems are operating within spec, run an injector buzz test.

Identifying a Clogged Oil Cooler

The pressure differential between EOT and ECT should not exceed 10 degrees F once the engine has reached operating temperature. If the temperature difference exceeds this by a wide margin, the oil cooler is likely clogged. Coolant blowing out of the degas bottle is a sign that the oil cooler has failed.

Identifying a Failed or Leaking EGR Cooler

Loss of engine coolant is the most prominent sign that an EGR cooler has failed. In extreme cases, steam will be emitted out of the tailpipe. A simple way to check the EGR cooler condition is to pull the EGR valve. If there is any white residue or white "crystals" stuck to the EGR valve, the cooler is leaking and needs to be replaced.

Identifying a Stuck Unison Ring or VGT Vanes

Manually command the VGT solenoid from the open to closed positions KOER using a scantool. Monitor MAP while listening for a change in turbocharger noise. If the VGT solenoid is unresponsive, unplug the solenoid. If there is still no change, it is likely that the unison rings and/or VGT vanes are mechanically stuck, preventing the VGT solenoid from changing their position.

6.0 Power Stroke Parts List - Common Service & Repair Items


Part Number(s)


Engine oil filter

Motorcraft FL-2016
Ford 3C3Z-6731-AA


Fuel filter set

Motorcraft FD-4616


EGR valve

Ford 3C3Z-9P455-AB


EGR valve gasket/seal kit

Ford 3C3Z-9P455-AB


EGR valve connector



ICP sensor

2003 - early 2004

Ford 3C3Z-9F838-EA


Late 2004 - 2007

Ford 4C3Z-9F838-A

ICP sensor connector

Ford 5C3Z-12224-A


IPR valve

2003 - early 2004

Ford 3C3Z-9C968-AA


Late 2004 - 2007

Ford 5C3Z-9C968-CA


IPR valve connector

Ford 6E7Z-12A690-DA


Camshaft position sensor (CPS)

Ford 8C3Z-12K073-A


Crankshaft position sensor (CKP)

Ford 3C3Z-6C315-AA


MAP sensor

Motorcraft CX-1961


EBP sensor

2003 - early 2004

Motorcraft DPFE-3


Late 2004 - 2007

Ford 5C3Z-9J460-B

EBP sensor tube

2003 - early 2004

Ford 3C3Z-9D477-BA


Late 2004 - 2007

Ford 5C3Z-9D477-A

EBP sensor connector

Ford 6E7Z-12A690-DA


VGT solenoid

Garrett 792593-0001


VGT solenoid connector

Ford 6E7Z-12A690-DA


Glow plug

2003 - early 2004

Motorcraft ZD-12


Late 2004 - 2007

Motorcraft ZD-13

Glow plug harness

2003 - early 2004

Driver side

Ford 3C3Z-12A690-AA


Passenger side

Ford 3C3Z-12A690-BA

Late 2004 - 2007

Driver side

Ford 5C3Z-12A690-A


Passenger side

Ford 4C2Z-12A690-AB

Fuel pressure regulator spring kit

Ford 3C3Z-9T517-AG
International 1854267C94


Turbocharger reinstall kit

Ford 3C3Z-9T514-AG


[1] - EGR valves become mechanically stuck far more often than they fail electronically; recommend cleaning and retesting before opting to replace the part entirely. Always inspect connector condition when diagnosing EGR related problems.
[2] - 2003 and early 2004 model year engines position the ICP sensor below the turbocharger and through the HPOP reservoir cover. Late 2004 model year engines position the ICP sensor on the passenger side valve cover. Always inspect connector condition when replacing sensor; if oil has entered the connector housing, a new connector pigtail should be installed.
[3] - Located through engine block on driver side of engine.
[4] -Located through engine block on passenger side of engine, mounted behind AC compressor.
[5] - While all model year engines feature this sensor, its readings are not used by the PCM for 2003 and early 2004 model years. Late 2004 and newer engine models rely on EBP sensor readings to manage vane position in the variable geometry turbocharger. EBP sensor tube should be cleaned and inspected at time of replacement.
[6] - 2003 and early 2004 glow plugs are longer and CANNOT be used in late 2004 and newer engines; they WILL contact the piston and cause severe damage. 9/29/2003 is the ENGINE build date cutoff. Note that early 2004 model year trucks received 2003 model year engines.
[7] - Solid busbar style harness; fits engines built 8/18/2003 and earlier.
[8] - Flexible "daisy chained" style harness; fits engines build 1/15/2004 and later.