1993 DODGE TRUCK Service Repair Manual

14
- 102
FUEL
SYSTEM
—

•
SYMPTOM

CAUSI
ACTION

lupin*
mimes under Im4 Incorrect
injection
pump
timing
Adjust
injection
pump
timing

Restricted
or
damaged
injector
nozzle
Replace
or
repair
as
necessary

Restricted
or
blocked
fuel
injection
lines Install
fittings
proper positions

Fuel
Injection
pump malfunction
or

not adjustable
Replace
fuel
injection
pump
lew power Improper
fuel
Drain
fuel
tank, flush
system,
fill
with

proper
fuel

Empty
fuel
tank or
fuel
tank vent blocked
Fill
tank, bleed
system,
check tank vent
Control lever not going
to full throttle
position Adjust
throttle
linkage

Clogged
fuel
filter
Replace
fuel
filter

Intercooler
internally
blocked
or
leaking
Check
pressure
drop
across
intercooler.
If
pressure
drop is more than
4
in.
Hg,
clean
or replace
as
necessary.

Restricted
or
blocked
fuel
supply lines
Remove
restrictions
or
replace lines

Injection
pump overflow
fitting
switched
with
inlet
fitting
Install
fittings
in
proper positions

Leaking
injection
lines, damaged lines
or
loose
connections
Replace
damaged
lines
or
tighten

connections
as
necessary.
Bleed
fuel
system
Incorrect
injection
pump
to
engine
timing
Adjust
injection
pump
timing

Restricted or
damaged
injector
nozzle
Repair
or replace as
necessary

Clogged
or
restricted
air filter
Remove
restrictions
or
replace
filter if

necessary

Air
fuel
control
tube broken
or
leaking
Repair
or replace
as
necessary

Low
manifold pressure
Check
and repair turbocharger operation.

Check
intercooler and
air
pipes
for
blockage

Injection
sequence
does
not correspond

with
firing
order Install
fuel
injection
lines in correct
order

Low
or
uneven
engine
compression
Repair
as
necessary

Restricted or blocked
fuel
injection
lines
Remove
restrictions
or
replace lines
Incorrect
injection
pump
to
engine
timing
Check
injection
pump
to
engine
timing

Fuel
injection
pump malfunction
or

not adjustable
Replace
fuel
injection
pump J9114-253
DIESEL
FUEL
INJECTION
SYSTEM
DIAGNOSIS-CONTINUED

FUEL
SYSTEM
14-103

DIESEL FUEL
INJECTION
SYSTEM DIAGNOSIS-CONTINUED

SYMPTOM
CAUSE
ACTION

Excessive
fuel
consumption improper diesel
fuel
Use
correct
fuel
for conditions. Refer
to

owner's manual
Incorrect injection pump timing
Adjust
injection pump timing
Restricted or damaged
injector
nozzle Repair or replace as necessary

Clogged
or
restricted air
filter
Remove
restrictions or replace air
filter
if

necessary

Injection sequence does not correspond

with
firing order install
fuel
injection lines in correct order
Intercooler internally blocked
or
leaking
Check
pressure drop
across
intercooler.

If
pressure drop
is
more than
4
in. Hg,
clean or replace as necessary

Low
idle misadjusted
Adjust
idle stop screw
Malfunctioning
KSB
valve
Replace
injection pump
Incorrect injection pump to engine timing
Adjust
injection pump to engine timing
Fuel injection pump malfunction or
not adjustable
Replace
fuel
injection pump
Unabie to shut engine off Voltage to
fuel
solenoid
interrupted
or
fuel

solenoid
inoperative Correct voltage supply problem or
replace

solenoid

Either poor
performance,
black moke
or
low power Improper
fuel

Drain
fuel
tank, flush
system,
fill
with

proper
fuel
for conditions. Refer to owner's
manual

Air
in
fuel
system
Bleed
fuel
system
Intercooler internally blocked
or
leaking
Check
pressure drop
across
intercooler.

If
pressure drop is more than
4
in. Hg,
clean
or
replace
as
necessary

Restricted or blocked
fuel
injection lines
Remove
restrictions or replace lines
Incorrect injection pump timing
Adjust
injection pump timing
Restricted or damaged
injector
nozzle
Repair
or replace as necessary

Clogged
or restricted air
filter
Remove
restrictions or replace
filter
if

necessary

Air
fuel
control tube leaking or broken Repair or replace as necessary

Low
manifold pressure
Check
and repair turbocharger operation
Injection sequence does not correspond

with
firing order Install
fuel
injection lines in correct order
—
Low
or uneven engine compression
Repair as necessary
J9114-255

14-104
FUEL
SYSTEM

• DIESEL FUEL INJECTION SYSTEM DIAGNOSIS-CONTINUED

SYMPTOM
CAUSE
ACTION

Either poor performance,

black
smoke
or low
power
Injection
pump
to engine timing
Fuel injection pump malfunction or
not adjustable
Check
injection
pump
to
engine
timing

Replace
fuel
injection pump
White or blue fog-like exhaust in full-load range Improper
fuel

Drain
fuel
tank,
flush
system,
fill
with proper
fuel,
change
filter

Empty
fuel
tank or
fuel
tank vent blocked
Fill
tank, bleed
system,
check tank vent

Air
in
fuel
system
Bleed
fuel
system

Clogged
fuel
filter
Replace
fuel
filter

Restricted
or blocked
fuel
injection lines
Remove
restriction or replace lines

Restricted
or blocked
fuel
supply lines
Remove
restriction or replace lines

Wax
buildup in
fuel
filter
(cold weather

only)
Replace
fuel
filter,
use
recommended
i
diesel fuel.
Inspect
fuel
heater electrical connector for
damage.

Incorrect injection pump to engine timing
Adjust
injection pump timing
Injection pump overflow fitting switched
with inlet fitting Install fittings in
proper
positions

Fuel injection pump malfunction or
not adjustable
Replace
fuel
injection pump
Incorrect lale speed
Low
idle misadjusted
Adjust
idle
stop
screw
Fuel injection pump malfunction or
not adjustable
Replace
fuel
injection pump

Engine
does
not rev up Improper
fuel
Drain
fuel
tank,
flush
system,
fill
with proper
fuel,
change
filter

Empty
fuel
tank or
fuel
tank
vent blocked
Fill
tank, bleed
system,
check
tank vent J9114-26

•

FUEL
SYSTEM
14-105 DIESEL FUEL INJECTION SYSTEM DIAGNOSIS-CONTINUED

SYMPTOM

CAUSE
ACTION

Engine
does not rev up Control lever not
going
to
full
throttle

position
Adjust
throttle
linkage

Air
in
fuel
system
Bleed
fuel
system
Intercooler internally blocked or leaking
Check
pressure drop
across
intercooler.
If pressure drop is more than 4 in. Hg,
clean or replace as necessary

Clogged
fuel
filter
Replace
fuel
filter

Restricted or blocked
fuel
supply lines
Remove
restrictions or replace lines

Wax
buildup in
fuel
filter
(cold weather only)
Inspect
fuel
heater
electrical
connector
for
damage.
Replace
fuel
filter,
use recommended diesel fuel.
Incorrect injection pump timing
Adjust
injection pump timing
Injection pump overflow
fitting
switched

with
inlet
fitting
Install fittings in proper sequence

Low
or uneven engine
compression
Repair
as
necessary
Fuel injection pump malfunction or
not adjustable
Replace
injection pump
Infection pump runs hot Overflow blocked
Clean
overflow orifice or replace
fitting

J9114-254

14
- 106
FUEL SYSTEi

DIESEL FUEL
INJECTION-SERVICE
PROCEDURES

INDEX

page

Air Bleed Procedure
106

Air Fuel Control Tube
107

Air Intake Heater
107
Engine
Speed
Sensor
108

Fuel Drain Manifold
109

Fuel Heater
. 110

Fuel
Injection
Pump
110

Fuel
Injection
Pump Supply Line
114

Fuel
Injectors
114

AIR BLEED PROCEDURE
A certain amount
of air
becomes trapped
in the

fuel system when fuel system components
are
ser­
viced
or
replaced. Bleed
the
system after fuel system service according
to the
following procedures.

WARNING:
DO NOT
BLEED
AIR
FROM
THE
FUEL
SYSTEM
OF
A
HOT
ENGINE.
DO
NOT
ALLOW FUEL
TO SPRAY ONTO
THE
EXHAUST MANIFOLD WHEN BLEEDING
AIR
FROM
THE
FUEL SYSTEM.

MANUAL BLEEDING
Some
air
enters
the
fuel system when
the
filters
or

injection pump supply line
are
changed. This small
amount
of air is
vented automatically from
the
injec­
tion pump through
the
fuel drain manifold. This
is if

the filter
was
changed according
to
instructions.
The system will have
to be
bleed manually
if:

•
The
fuel filter
is not
filled before installation

•
Injection pump
is
replaced

•
High pressure fuel line connections
are
loosened
or
lines replaced

•
Initial engine start-up
or
start-up after
an ex­

tended period
of no
engine operation. (1) Open
the low
pressure bleed screw
(Fig. 1).
(2) Operate
the
hand lever
on the
mechanical lift
pump until
the
fuel exiting
the low
pressure bleed screw
is
free
of air.
If
the
manual lever feels
as if it is not
pumping,
ro­

tate (crank)
the
engine approximately
90
degrees. Continue pumping until
air is
removed. (3) Tighten
low
pressure bleed screw
to 8 N»m (6

ft.
lbs.)
torque.

CAUTION:
The
manual lever must
be
returned
to

the lock position
(up) after
priming.

INJECTION
PUMP

WARNING:
THE
ENGINE
MAY
START WHEN
CRANKING
TO
BLEED
AIR
FROM
THE
INJECTION
page

Fuel/Water Separator
Filter
................
115

High
Pressure Fuel Lines
116
Injection
Timing
117

KSB
Solenoid
118

Mechanical
Lift
Pump
119

Powertrain Control Module (PCM)
108

Throttle
Position
Sensor
(TPS)
119
Water-ln-Fuel
Sensor
121
Fig.
1
Low
Pressure
Bleed Screw

PUMP.
PLACE
THE
TRANSMISSION
IN
NEUTRAL

OR
PARK
AND SET
PARKING BRAKE BEFORE
EN­

GAGING
THE
STARTER MOTOR.
CAUTION:
Do
not
engage
the
starter
motor
for
more
than
30
seconds
at a
time.
Allow
two
minutes
be­

tween cranking intervals.

Crank
the
engine
for 30
seconds
at a
time
to
allow
air trapped
in the
injection pump
to
vent
out the

drain manifold. Observe
the
previous WARNING
and

CAUTION.
HIGH PRESSURE FUEL LINES

WARNING:
THE
INJECTION PUMP SUPPLIES HIGH
PRESSURE
FUEL
OF
APPROXIMATELY
59,000
KPA

(8,000
PSI) TO
EACH INDIVIDUAL INJECTOR
THROUGH
THE
HIGH
PRESSURE
LINES. FUEL
UN­
DER
THIS AMOUNT
OF
PRESSURE
CAN
PENE­
TRATE
THE
SKIN
AND
CAUSE PERSONAL INJURY. WEAR SAFETY GOGGLES
AND
ADEQUATE PRO­
TECTIVE CLOTHING
AND
AVOID CONTACT
WITH

FUEL SPRAY WHEN BLEEDING HIGH
PRESSURE
FUEL LINES.

•
FUEL SYSTEM 14 - 107
WARNING;
DO NOT
BLEED
AIR
FROM
THE
FUEL

SYSTEM
OF A HOT
ENGINE.
DO NOT
ALLOW FUEL
TO SPRAY ONTO
THE
EXHAUST MANIFOLD WHEN
BLEEDING
AIR
FROM
THE
FUEL SYSTEM.

Bleed air from one injector at time. (1) Loosen the high pressure fuel line fitting at the
injector (Fig. 2).

Fig.
2
Bleeding
High Pressure Fuel Lines

(2) Crank the engine until all air is bleed from the

line.
Do not operate the starter motor for longer
than 30 seconds. Wait two minutes between cranking intervals.
(3) Start the engine and bleed one injector at a
time until the engine runs smoothly.

AIR
FUEL CONTROL TUBE
REMOWAL
(1) Disconnect tube from fuel injection pump (Fig.

3). Fig.
3 Air
Fuel
Control Tube Removal/Installation
(2) Disconnect tube from intake manifold.
(3) Remove tube. Discard seals.
INSTALLATION

(1) Connect tube to intake manifold. Tighten fit­
ting to 8 Nnn (6 ft. lbs.) torque. (2) Connect tube to injection pump using new

seals.
Tighten fitting screw to 12 Nnn (9 ft. lbs.)
torque.

AIR INTAKE HEATER
(1) Disconnect negative cable from battery.
(2) Disconnect the throttle rod from the throttle le­
ver on the injection pump. (3) Disconnect electrical connections air intake
heaters (Fig. 4).

Fig.
4 Air Intake Heaters—Typical
(4) Remove the throttle bracket (Fig. 5).

Fig.
5
Throttle
Bracket—Typical
(5) Loosen clamps securing air the crossover tube
hose to the turbo-charger.
(6) Remove air crossover tube mounting screws.
(7) Remove air crossover tube.
(8) Remove air intake heater.
(9) Clean air intake heater-to-intake manifold
mating surfaces.

(10) Install air intake heater (with new gasket) in
reverse order of removal.
AIR
INTAKE
HE
A TER
RELA YS
(1) Disconnect negative cable from battery.
(2) Disconnect electrical connections from relays
(Fig. 6).

HEATER
RELAYS
WHEEL..
WELL
J9114-67

Fig. 6 Air intake Heater Relays—Typical (3) Remove relay mounting screws. Remove relays.
(4) Install relays in reverse order of removal.

POWERTRAIN CONTROL MODULE
(PCI)
REMOWAL The PCM is located in the engine compartment be­
hind the battery and under the left front fender (Fig.
7).
TORQUE CONVERTER
CLUTCH RELAY A/C CLUTCH RELAY STARTER RELAY
AUTO SHUTDOWN RELAY FUEL PUMP RELAY DATA LINK
CONNECTOR POWERTRAIN
CONTROL

MODULE
J9314-164

Fig. 7 Powertrain Control
Module
(PCM) Location (1) Disconnect the negative battery cable at bat­
tery.
(2) Remove battery holddown clamps.
(3) Position battery to gain access to PCM,
(4) Remove 60-way electrical connector from the
PCM (one screw) (Fig. 8).
PCM
MOUNTING BOLTS
PCM CONNECTOR CONNECTOR MOUNTING
BOLT
J9314-165

Fig. 8 PCM Mounting (5) Remove the three PCM-to-mounting bracket
bolts (Fig. 8). Do not remove the PCM mounting
bracket from the fender.
(6) Remove PCM from vehicle.
INSTALLATION (1) Check pins in 60-way PCM connector for dam­

age.
Repair as necessary.
(2) Position PCM and install mounting bolts.
Tighten bolts to 4 N*m (35 in. lbs.) torque.
(3) Connect 60-way electrical connector to the
PCM. Tighten connector mounting screw to 4 N#m (35 in. lbs.) torque. (4) Install battery. (5) Connect battery cable to battery.

ENGINE
SPEED SENSOR
The engine speed sensor (sometimes referred to as
the crankshaft position sensor) is located on the front of engine (Fig. 9). Two spacers located behind the
sensor are used to position sensor over the vibration
damper.
REMOWAL Before removing the sensor, note the position and
routing of the sensor wiring harness. This routing must be maintained to prevent wiring from contact­
ing belt or pulleys.
(1) Disconnect the speed sensor pigtail harness
from the main engine wiring harness near the front/
top of engine.
(2) Remove the clip bolts from the sensor pigtail
wiring harness. (3) Remove the two speed sensor mounting nuts
(Fig. 9).

SENSOR
MOUNTING BOLTS
VIBRATION
DAMPER
J9214-69

Fig.
9
Engine Speed Sensor
(4) Remove the speed sensor and its two mounting
spacers from the vehicle.

INST
ALL A
TION/ADJUSTMENT
The engine speed sensor uses a slotted hole on one
side (Fig. 10) to adjust its depth. A brass (non-mag­
netic) feeler gauge must be used to adjust the sensor.

Fig.
10
Engine Speed
Sensor—Installation
Sensor-to-vibration damper air gap is: 1.25 MM
(.049 in.) minimum to 1.30 MM (.051 in.) maximum.
(2) Position speed sensor, its two mounting spacers
and two mounting nuts to the engine. Install mount­
ing nuts finger tight.
(3) Route sensor wiring harness behind engine pul­

leys.
Install and tighten wiring harness clip bolts. (4) Place the feeler gauge between the sensor and
the vibration dampener. (5) Gently seat (push down) the sensor until it con­
tacts the feeler gauge. Be sure the sensor is not
near either of the notches (Fig. 9) on the vibra­
tion damper. If sensor is adjusted at or near
these notches, it will be damaged when engine is started.
(6) Tighten sensor mounting nuts to 24 N#m (18 ft.
lbs.) torque.
(7) Remove feeler gauge.
(8) Connect the sensor electrical connector to the
main engine wiring harness.

FUEL
DRAIN
MANIFOLD
REMOVAL
(1) Remove the fuel drain manifold holddown
clamp mounting screws (Fig. 11).

DRAIN

MANIFOLD

J9114-43
Fig.
11
Fuel
Drain Manifold
(2) Remove injection pump vent capscrew (Fig. 11).
(3) Remove fuel drain manifold fitting screws and
washers at each fuel injector (Fig. 12).
INJECTOR

DRAIN
MANIFOLD
FITTING
SCREW
J9114-44
Fig.
12
Fuel
Drain
Fitting
Screws

(4) Disconnect drain line T-fittings.