check engine DODGE RAM 2003 Service Repair Manual

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐENGINE OIL
LEAKS
Begin with a through visual inspection of the
engine, particularly at the area of the suspected leak.
If an oil leak source is not readily identifiable, the
following steps should be followed:
(1) Do not clean or degrease the engine at this
time because some solvents may cause rubber to
swell, temporarily stopping the leak.
(2) Add an oil-soluble dye (use as recommended by
manufacturer). Start the engine and let idle for
approximately 15 minutes. Check the oil dipstick to
be sure the dye is thoroughly mixed as indicated
with a bright yellow color under a black light source.
(3) Using a black light, inspect the entire engine
for fluorescent dye, particularly at the suspected area
of oil leak. If the oil leak is found and identified,
repair per service manual instructions.
(4) If dye is not observed, drive the vehicle at var-
ious speeds for approximately 24km (15 miles), and
repeat previous step.
(5) If the oil leak source is not positively identified
at this time, proceed with the air leak detection test
method as follows:
(6) Disconnect the breather cap to air cleaner hose
at the breather cap end. Cap or plug breather cap
nipple.
(7) Remove the PCV valve from the cylinder head
cover. Cap or plug the PCV valve grommet.
(8) Attach an air hose with pressure gauge and
regulator to the dipstick tube.
CAUTION: Do not subject the engine assembly to
more than 20.6 kpa (3 PSI) of test pressure.
(9) Gradually apply air pressure from 1 psi to 2.5
psi maximum while applying soapy water at the sus-
pected source. Adjust the regulator to the suitable
test pressure that provide the best bubbles which
will pinpoint the leak source. If the oil leak is
detected and identified, repair per service manual
procedures.
(10) If the leakage occurs at the rear oil seal area,
refer to the section, Inspection for Rear Seal Area
Leak.
(11) If no leaks are detected, turn off the air sup-
ply and remove the air hose and all plugs and caps.
Install the PCV valve and breather cap hose. Proceed
to next step.
(12) Clean the oil off the suspect oil leak area
using a suitable solvent. Drive the vehicle at various
speeds approximately 24 km (15 miles). Inspect the
engine for signs of an oil leak by using a black light.
DIAGNOSIS AND TESTINGÐENGINE OIL
PRESSURE
(1) Remove oil pressure sending unit.
(2) Install Oil Pressure Line and Gauge Tool
C-3292. Start engine and record pressure. (Refer to 9
- ENGINE - SPECIFICATIONS).
OIL
STANDARD PROCEDURE - ENGINE OIL
OIL LEVEL INDICATOR (DIPSTICK)
The engine oil level indicator is located at the right
front of the engine, left of the generator (Fig. 53).
CRANKCASE OIL LEVEL INSPECTION
CAUTION: Do not overfill crankcase with engine oil,
oil foaming and oil pressure loss can result.
To ensure proper lubrication of an engine, the
engine oil must be maintained at an acceptable level.
The acceptable levels are indicated between the ADD
and SAFE marks on the engine oil dipstick.
(1) Position vehicle on level surface.
(2) With engine OFF, allow approximately ten min-
utes for oil to settle to bottom of crankcase, remove
engine oil dipstick.
(3) Wipe dipstick clean.
(4) Install dipstick and verify it is seated in the
tube.
(5) Remove dipstick, with handle held above the
tip, take oil level reading.
Fig. 53 Oil Level Indicator Location
1 - CYLINDER HEAD COVER
2 - ENGINE OIL FILL CAP
3 - DIPSTICK
4 - ENGINE OIL FILTER
5 - FILTER BOSS
DRENGINE - 5.9L 9 - 269
LUBRICATION (Continued)

OIL PUMP
REMOVAL
(1) Remove the oil pan (Refer to 9 - ENGINE/LU-
BRICATION/OIL PAN - REMOVAL).
(2) Remove the oil pump from rear main bearing
cap.
DISASSEMBLY
(1) Remove the relief valve as follows:
(a) Remove cotter pin. Drill a 3.175 mm (1/8
inch) hole into the relief valve retainer cap and
insert a self-threading sheet metal screw.
(b) Clamp screw into a vise and while support-
ing oil pump, remove cap by tapping pump body
using a soft hammer. Discard retainer cap and
remove spring and relief valve (Fig. 58).
(2) Remove oil pump cover (Fig. 59).
(3) Remove pump outer rotor and inner rotor with
shaft (Fig. 59).
(4) Wash all parts in a suitable solvent and inspect
carefully for damage or wear.
INSPECTION
Mating surface of the oil pump cover should be
smooth. Replace pump assembly if cover is scratched
or grooved.
Lay a straightedge across the pump cover surface
(Fig. 60). If a 0.038 mm (0.0015 inch) feeler gauge
can be inserted between cover and straightedge,
pump assembly should be replaced.
Fig. 58 Oil Pressure Relief Valve
1 - OIL PUMP ASSEMBLY
2 - COTTER PIN
3 - RELIEF VALVE
4 - RETAINER CAP
5 - SPRING
Fig. 59 Oil Pump
1 - INNER ROTOR AND SHAFT
2 - BODY
3 - DISTRIBUTOR DRIVESHAFT (REFERENCE)
4 - COTTER PIN
5 - RETAINER CAP
6 - SPRING
7 - RELIEF VALVE
8 - LARGE CHAMFERED EDGE
9 - BOLT
10 - COVER
11 - OUTER ROTOR
Fig. 60 Checking Oil Pump Cover Flatness
1 - COVER
2 - STRAIGHT EDGE
3 - FEELER GAUGE
9 - 272 ENGINE - 5.9LDR

WARNING: USE EXTREME CAUTION WHEN THE
ENGINE IS OPERATING. DO NOT STAND IN A
DIRECT LINE WITH THE FAN. DO NOT PUT YOUR
HANDS NEAR THE PULLEYS, BELTS, OR THE FAN.
DO NOT WEAR LOOSE CLOTHING.
(1) Start the engine.
(2) Spray a small stream of water at the suspected
leak area.
(3) If a change in RPMs occur, the area of the sus-
pected leak has been found.
(4) Repair as required.
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Drain the cooling system (Refer to 7 - COOL-
ING - STANDARD PROCEDURE).
(3) Remove the A/C compressor (Refer to 24 -
HEATING & AIR CONDITIONING/PLUMBING/A/C
COMPRESSOR - REMOVAL).
(4) Remove the generator (Refer to 8 - ELECTRI-
CAL/CHARGING/GENERATOR - REMOVAL).
(5) Remove the accessory drive bracket.
(6) Remove the air cleaner.
(7) Perform the Fuel System Pressure release pro-
cedure (Refer to 14 - FUEL SYSTEM/FUEL DELIV-
ERY - STANDARD PROCEDURE). Disconnect the
fuel lines (Refer to 14 - FUEL SYSTEM/FUEL
DELIVERY/QUICK CONNECT FITTING - STAN-
DARD PROCEDURE).
(8) Disconnect the accelerator linkage (Refer to 14
- FUEL SYSTEM/FUEL INJECTION/THROTTLE
CONTROL CABLE - REMOVAL) and if so equipped,
the speed control and transmission kickdown cables.
(9) Remove the return spring.
(10) Remove the distributor cap and wires.
(11) Disconnect the coil wires.
(12) Disconnect the heat indicator sending unit
wire.
(13) Disconnect the heater hoses and bypass hose.
(14) Remove the closed crankcase ventilation and
evaporation control systems.
(15) Remove intake manifold bolts.
(16) Lift the intake manifold and throttle body out
of the engine compartment as an assembly.
(17) Remove and discard the flange side gaskets
and the front and rear end seals.
(18) Remove the throttle body bolts and lift the
throttle body off the intake manifold (Fig. 68). Dis-
card the gasket.
(19) If required, remove the plenum pan and gas-
ket. Discard gasket.
CLEANING
Clean manifold in solvent and blow dry with com-
pressed air.Clean cylinder block gasket surfaces using a suit-
able solvent.
The plenum pan rail must be clean and dry (free of
all foreign material).
INSPECTION
Inspect manifold for cracks.
Inspect mating surfaces of manifold for flatness
with a straightedge.
INSTALLATION
(1) If removed, position new plenum gasket and
install plenum pan (Fig. 69).
(2) Tighten plenum pan mounting bolts as follows:
²Step 1. Tighten bolts to 5.4 N´m (48 in. lbs.)
²Step 2. Tighten bolts to 9.5 N´m (84 in. lbs.)
²Step 3. Check all bolts are at 9.5 N´m (84 in.
lbs.)
(3) Install the flange gaskets. Ensure that the ver-
tical port alignment tab is resting on the deck face of
the block. Also the horizontal alignment tabs must be
in position with the mating cylinder head gasket tabs
(Fig. 71). The words MANIFOLD SIDE should be vis-
ible on the center of each flange gasket.
(4) Apply MopartGEN II Silicone Rubber Adhe-
sive Sealant, or equivalent, to the four corner joints.
An excessive amount of sealant is not required to
ensure a leak proof seal. However, an excessive
amount of sealant may reduce the effectiveness of
the flange gasket. The sealant should be approxi-
mately 5 mm (0.2 in) in diameter and 15 mm (0.6 in.)
long.
Fig. 68 Throttle Body Assembly
1 - FUEL RAIL ASSEMBLY
2 - FUEL RAIL MOUNTING BOLTS
3 - FUEL RAIL CONNECTING HOSES
DRENGINE - 5.9L 9 - 275
INTAKE MANIFOLD (Continued)

(5)Install the front and rear end seals (Fig. 70) Make
sure the molded dowel pins on the end seals fully enter the
corresponding holes in the cylinder block.
(6)Carefully lower intake manifold into position on
the cylinder block and cylinder heads. After intake man-
ifold is in place, inspect to make sure seals are in place.
(7) Using a new gasket, install the throttle body
onto the intake manifold. Tighten the bolts to 23 N´m
(200 in. lbs.) torque.(8) Install the intake manifold bolts and tighten as
follows (Fig. 72):
²Step 1. Tighten bolts 1 through 4 to 8 N´m (72
in. lbs.) Tighten in alternating steps 1.4 N´m (12 in.
lbs.) at a time
²Step 2. Tighten bolts 5 through 12 to 8 N´m (72
in. lbs.)
²Step 3. Check all bolts are torqued to 8 N´m (72
in. lbs.)
²Step 4. Tighten all bolts in sequence to 16 N´m
(12 ft. lbs.)
²Step 5. Check all bolts are torqued to 16 N´m
(12 ft. lbs.)
(9) Install closed crankcase ventilation and evapo-
ration control systems.
(10) Connect the coil wires.
(11) Connect the heat indicator sending unit wire.
(12) Connect the heater hoses and bypass hose.
(13) Install distributor cap and wires.
(14) Hook up the return spring.
(15) Connect the accelerator linkage (Refer to 14 -
FUEL SYSTEM/FUEL INJECTION/THROTTLE
CONTROL CABLE - INSTALLATION) and if so
Fig. 69 Plenum Pan Bolt Tightening Sequence
Fig. 70 Front and Rear End Seals
1 - FRONT CROSS-OVER GASKET
2 - REAR CROSS-OVER GASKET
Fig. 71 Intake Manifold Flange Gasket Alignment
1 - FLANGE GASKET
2 - ALIGNMENT TABS
3 - CYLINDER HEAD GASKET
9 - 276 ENGINE - 5.9LDR
INTAKE MANIFOLD (Continued)

(5) Assemble exhaust pipe to manifold and secure
with bolts, nuts and retainers. Tighten the bolts and
nuts to 34 N´m (25 ft. lbs.) torque.
(6) Lower the vehicle.
(7) Connect the negative cable to the battery.
TIMING BELT / CHAIN
COVER(S)
REMOVAL
(1) Disconnect the negative cable from the battery.
(2) Remove water pump (Refer to 7 - COOLING/
ENGINE/WATER PUMP - REMOVAL).
(3) Remove power steering pump (Refer to 19 -
STEERING/PUMP - REMOVAL).
(4) Remove vibration damper (Refer to 9 -
ENGINE/ENGINE BLOCK/VIBRATION DAMPER -
REMOVAL).
(5) Loosen oil pan bolts and remove the front bolt
at each side.
(6) Remove the cover bolts.
(7) Remove chain case cover and gasket using
extreme caution to avoid damaging oil pan gasket.
INSTALLATION
(1) Be sure mating surfaces of chain case cover
and cylinder block are clean and free from burrs.
(2) The water pump mounting surface must be
cleaned.
(3) Using a new cover gasket, carefully install
chain case cover to avoid damaging oil pan gasket.
Use a small amount of MopartSilicone Rubber Adhe-
sive Sealant, or equivalent, at the joint between tim-
ing chain cover gasket and the oil pan gasket. Finger
tighten the timing chain cover bolts at this time.NOTE: Special Tool 6635 must be used to align the
front cover and seal with the crankshaft.
(4) Position the special tool 6635 onto the crank-
shaft (Fig. 75).
(5) Tighten chain case cover bolts to 41 N´m (30
ft.lbs.) torque. Tighten oil pan bolts to 24 N´m (215
in. lbs.) torque.
(6) Remove special tool 6635.
(7)
Inspect the seal flange on the vibration damper.
(8) Install vibration damper (Refer to 9 - ENGINE/
ENGINE BLOCK/VIBRATION DAMPER - INSTAL-
LATION).
(9) Install water pump and housing assembly
using new gaskets (Refer to 7 - COOLING/ENGINE/
WATER PUMP - INSTALLATION).
(10) Install power steering pump (Refer to 19 -
STEERING/PUMP - INSTALLATION).
(11) Install the serpentine belt (Refer to 7 - COOL-
ING/ACCESSORY DRIVE/DRIVE BELTS - INSTAL-
LATION).
(12) Install the cooling system fan (Refer to 7 -
COOLING/ENGINE/RADIATOR FAN - INSTALLA-
TION).
(13) Position the fan shroud and install the bolts.
Tighten the bolts to 11 N´m (95 in. lbs.) torque.
(14) Fill cooling system (Refer to 7 - COOLING -
STANDARD PROCEDURE).
(15) Connect the negative cable to the battery.
(16) Start engine check for leaks.
Fig. 74 Engine Exhaust Manifold Installation - 5.9L
Engines
1 - EXHAUST MANIFOLD (LEFT)
2 - BOLTS & WASHERS
3 - NUTS & WASHERS
4 - EXHAUST MANIFOLD (RIGHT)
5 - BOLTS & WASHERS
Fig. 75 Position Special Tool 6635 onto Crankshaft
1 - SPECIAL TOOL 6635
2 - OIL SEAL
3 - TIMING CHAIN COVER
9 - 278 ENGINE - 5.9LDR
EXHAUST MANIFOLD (Continued)

TIMING BELT/CHAIN AND
SPROCKETS
REMOVAL
(1) Disconnect battery negative cable.
(2) Remove Timing Chain Cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - REMOVAL).
(3) Re-install the vibration damper bolt finger
tight. Using a suitable socket and breaker bar, rotate
the crankshaft to align timing marks as shown in
(Fig. 76).
(4) Remove camshaft sprocket attaching bolt and
remove timing chain with crankshaft and camshaft
sprockets.
INSPECTIONÐMEASURING TIMING CHAIN
STRETCH
(1) Place a scale next to the timing chain so that
any movement of the chain may be measured.
(2) Place a torque wrench and socket over cam-
shaft sprocket attaching bolt. Apply torque in the
direction of crankshaft rotation to take up slack; 41
N´m (30 ft. lbs.) torque with cylinder head installed
or 20 N´m (15 ft. lbs.) torque with cylinder head
removed. With a torque applied to the camshaft
sprocket bolt, crankshaft should not be permitted to
move. It may be necessary to block the crankshaft to
prevent rotation.
(3) Hold a scale with dimensional reading even
with the edge of a chain link. With cylinder heads
installed, apply 14 N´m (30 ft. lbs.) torque in the
reverse direction. With the cylinder heads removed,
apply 20 N´m (15 ft. lbs.) torque in the reverse direc-
tion. Note the amount of chain movement (Fig. 77).
(4) Install a new timing chain, if its movement
exceeds 3.175 mm (1/8 inch).
INSTALLATION
(1) Place both camshaft sprocket and crankshaft
sprocket on the bench with timing marks on exactimaginary center line through both camshaft and
crankshaft bores.
(2) Place timing chain around both sprockets.
(3) Turn crankshaft and camshaft to line up with
keyway location in crankshaft sprocket and in cam-
shaft sprocket.
(4) Lift sprockets and chain (keep sprockets tight
against the chain in position as described).
(5) Slide both sprockets evenly over their respec-
tive shafts and use a straightedge to check alignment
of timing marks (Fig. 78).
(6) Install the camshaft bolt. Tighten the bolt to 68
N´m (50 ft. lbs.) torque.
(7) Check camshaft end play. The end play should
be 0.051-0.152 mm (0.002-0.006 inch) with a new
thrust plate and up to 0.254 mm (0.010 inch) with a
used thrust plate. If not within these limits install a
new thrust plate.
(8) Install the timing chain cover (Refer to 9 -
ENGINE/VALVE TIMING/TIMING BELT / CHAIN
COVER(S) - INSTALLATION).
Fig. 76 Alignment of Timing Marks
1 - TIMING MARKS
Fig. 77 Measuring Timing Chain Stretch
1 - TORQUE WRENCH
2 - 3.175 MM
(0.125 IN.)
Fig. 78 Alignment of Timing Marks
1 - TIMING MARKS
DRENGINE - 5.9L 9 - 279

DIAGNOSIS AND TESTING
DIAGNOSIS AND TESTINGÐENGINE DIAGNOSIS - MECHANICAL
CONDITION POSSIBLE CAUSES CORRECTION
LUBRICATING OIL
PRESSURE LOW1. Low oil level. 1. (a) Check and fill with clean engine oil.
(b) Check for a severe external oil leak that
could reduce the pressure.
2. Oil viscosity thin, diluted or wrong
specification.2. (a) Verify the correct engine oil is being
used. (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
2. (b) Look for reduced viscosity from fuel
dilution.
3. Improperly operating pressure
switch/gauge.3. Verify the pressure switch is functioning
correctly. If not, replace switch/gauge.
4. Relief valve stuck open. 4. Check/replace valve.
6. If cooler was replaced, shipping
plugs may have been left in cooler6. Check/remove shipping plugs.
7. Worn oil pump. 7. Check and replace oil pump.
8. Suction tube loose or seal leaking. 8. Check and replace seal.
9. Loose main bearing cap. 9. Check and install new bearing. Tighten
cap to proper torque.
10. Worn bearings or wrong bearings
installed.10. Inspect and replace connecting rod or
main bearings. Check and replace directed
piston cooling nozzles.
11. Directed piston cooling nozzles
under piston, bad fit into main
carrier.11. Check directed piston cooling nozzles
position.
12. Loose oil rifle plug with saddle-jet
style nozzles12.Tighten oil rifle plug.
13. Loose directed piston cooling
nozzle.13. Tighten directed piston cooling nozzle.
14. Both J-jet and saddle jet style
cooling nozzle installed.14. Install correct style jet.
LUBRICATING OIL
PRESSURE TOO HIGH1. Pressure switch/gauge not
operating properly.1. Verify pressure switch is functioning
correctly. If not, replace switch/gauge.
2. Engine running too cold. 2. Refer to Coolant Temperature Below
Normal (Refer to 7 - COOLING -
DIAGNOSIS AND TESTING).
3. Oil viscosity too thick. 3. Make sure the correct oil is being used.
(Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
4. Oil pressure relief valve stuck
closed or binding4. Check and replace valve.
DRENGINE 5.9L DIESEL 9 - 283
ENGINE 5.9L DIESEL (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
LUBRICATING OIL LOSS 1. External leaks. 1. Visually inspect for oil leaks. Repair as
required.
2. Crankcase being overfilled. 2. Verify that the correct dipstick is being
used.
3. Incorrect oil specification or
viscosity.3. (a) Make sure the correct oil is being
used (Refer to LUBRICATION &
MAINTENANCE/FLUID TYPES -
DESCRIPTION).
(b) Look for reduced viscosity from dilution
with fuel.
(c) Review/reduce oil change intervals.
4. Oil cooler leak 4. Check and replace the oil cooler.
5. High blow-by forcing oil out the
breather.5. Check the breather tube area for signs of
oil loss. Perform the required repairs.
6. Turbocharger leaking oil to the air
intake.6. Inspect the air ducts for evidence of oil
transfer. Repair as required.
COMPRESSION KNOCKS 1. Air in the fuel system. 1. Identify location of air leak and repair. Do
not bleed high pressure fuel system.
2. Poor quality fuel or water/gasoline
contaminated fuel.2. Verify by operating from a temporary
tank with good fuel. Clean and flush the
fuel tank. Replace fuel/water separator filter.
3. Engine overloaded. 3. Verify the engine load rating is not being
exceeded.
4. Improperly operating injectors. 5. Check and replace misfiring/inoperative
injectors.
EXCESSIVE VIBRATION 1. Loose or broken engine mounts. 1. Replace engine mounts.
2. Damaged fan or improperly
operating accessories.2. Check and replace the vibrating
components.
3. Improperly operating vibration
damper3. Inspect/replace vibration damper.
4. Improperly operating electronically
controlled viscous fan drive.4. Inspect/replace fan drive.
5. Worn or damaged generator
bearing.5. Check/replace generator.
6. Flywheel housing misaligned. 6. Check/correct flywheel alignment.
7. Loose or broken power
component.7. Inspect the crankshaft and rods for
damage that causes an unbalance
condition. Repair/replace as required.
8. Worn or unbalanced driveline
components.8. Check/repair driveline components.
EXCESSIVE ENGINE
NOISES1. Drive belt squeal, insufficient
tension or abnormally high loading.1. Check the automatic tensioner and
inspect the drive belt. Make sure water
pump, tensioner pulley, fan hub, generator
and power steering pump turn freely.
2. Intake air or exhaust leaks. 2. Refer to Excessive Exhaust Smoke
(Refer to 9 - ENGINE - DIAGNOSIS AND
TESTING).
9 - 284 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)

CONDITION POSSIBLE CAUSES CORRECTION
3. Excessive valve lash. 3. Adjust valves. Make sure the push rods
are not bent and rocker arms, adjusting
screws, crossheads, are not severely worn.
Replace bent or severely worn components.
4. Turbocharger noise. 4. Check turbocharger impeller and turbine
wheel for housing contact. Repair/replace
as required.
5. Gear train noise. 5. Visually inspect and measure gear
backlash. Replace gears as required.
6. Power function knock. 6. Check/replace rod and main bearings.
DIAGNOSIS AND TESTINGÐSMOKE
DIAGNOSIS CHARTS
The following charts include possible causes and
corrections forexcess or abnormalexhaust smoke.Small amounts of exhaust smoke (at certain times)
are to be considered normal for a diesel powered
engine.
EXCESSIVE BLACK SMOKE
POSSIBLE CAUSE CORRECTION
Air filter dirty or plugged. Check Filter MinderTat air filter (Refer to 9 - ENGINE/
AIR INTAKE SYSTEM/AIR CLEANER ELEMENT -
REMOVAL).
Air intake system restricted. Check entire air intake system including all hoses and
tubes for restrictions, collapsed parts or damage.
Repair/replace as necessary.
Air Leak in Intake System. Check entire air intake system including all hoses and
tubes for cracks, loose clamps and/or holes in rubber
ducts. Also check intake manifold for loose mounting
hardware.
Diagnostic Trouble Codes (DTC's) active or multiple,
intermittent DTC's.Refer to Powertrain Diagnostic Procedures Information.
Engine Control Module (ECM) not calibrated or ECM
has incorrect calibration.Refer to Powertrain Diagnostic Procedures Information.
Exhaust system restriction is above specifications. Check exhaust pipes for damage/restrictions. Repair as
necessary.
Fuel grade is not correct or fuel quality is poor. Temporarily change fuel brands and note condition.
Change brand if necessary.
Fuel injection pump malfunctioning. A DTC may have been set. If so, refer to Powertrain
Diagnostic Procedures Information.
Fuel injector malfunctioning. A DTC may have been set. Perform9Cylinder Cutout
Test9using DRB scan tool to isolate individual
cylinders. Also refer to Powertrain Diagnostic
Procedures Information and, to (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
DIAGNOSIS AND TESTING).
Fuel return system restricted. Check fuel return lines for restriction (Refer to 14 -
FUEL SYSTEM/FUEL DELIVERY - DIAGNOSIS AND
TESTING).
Intake manifold restricted. Remove restriction.
DRENGINE 5.9L DIESEL 9 - 285
ENGINE 5.9L DIESEL (Continued)

EXCESSIVE BLACK SMOKE
POSSIBLE CAUSE CORRECTION
Manifold Air Pressure (Boost) Sensor or sensor circuit
malfunctioning.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Raw fuel in intake manifold. Fuel injectors leaking on engine shutdown. Do Fuel
Injector Test (Refer to 14 - FUEL SYSTEM/FUEL
INJECTION/FUEL INJECTOR - DIAGNOSIS AND
TESTING).
Turbocharger air intake restriction. Remove restriction.
Turbocharger damaged. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
Turbocharger has excess build up on compressor
wheel and/or diffuser vanes.(Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - CLEANING).
Turbocharger wheel clearance out of specification. (Refer to 11 - EXHAUST SYSTEM/TURBOCHARGER
SYSTEM/TURBOCHARGER - INSPECTION).
EXCESSIVE WHITE SMOKE
POSSIBLE CAUSE CORRECTION
Air in fuel supply: Possible leak in fuel supply side
(between transfer pump and fuel tank module).(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/FUEL
TRANSFER PUMP - DIAGNOSIS AND TESTING).
Coolant leaking into combustion chamber. Do pressure test of cooling system (Refer to 7 -
COOLING - DIAGNOSIS AND TESTING).
Diagnostic Trouble Codes (DTC's) active or multiple,
intermittent DTC's.Refer to Powertrain Diagnostic Procedures Information.
In very cold ambient temperatures, engine block heater
is malfunctioning (if equipped).(Refer to 7 - COOLING/ENGINE/ENGINE BLOCK
HEATER - REMOVAL).
Engine coolant temperature sensor malfunctioning. A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information. Also check
thermostat operation (Refer to 7 - COOLING/ENGINE/
ENGINE COOLANT THERMOSTAT - DIAGNOSIS AND
TESTING).
Engine Control Module (ECM) not calibrated or has
incorrect calibration.A DTC should have been set. Refer to Powertrain
Diagnostic Procedures Information.
Fuel filter plugged. Refer to Powertrain Diagnostic Manual for fuel system
testing.
Fuel grade not correct or fuel quality is poor. Temporarily change fuel brands and note condition.
Change brand if necessary.
Fuel heater element or fuel heater temperature sensor
malfunctioning. This will cause wax type build-up in fuel
filter.Refer to Fuel Heater Testing (Refer to 14 - FUEL
SYSTEM/FUEL DELIVERY/FUEL HEATER -
DIAGNOSIS AND TESTING).
Fuel injector malfunctioning. A DTC should have been set. Perform9Cylinder cutout
Test9using DRB scan tool to isolate individual
cylinders. Also refer to Powertrain Diagnostic
Procedures Information and, (Refer to 14 - FUEL
SYSTEM/FUEL INJECTION/FUEL INJECTOR -
DIAGNOSIS AND TESTING).
Fuel injector hold-downs loose. Torque to specifications.
9 - 286 ENGINE 5.9L DIESELDR
ENGINE 5.9L DIESEL (Continued)