air filter DODGE TRUCK 1993 Service Owners Manual

•

EMISSION
CONTROL
SYSTEMS
25 - 9 (4) Turn engine off and remove PCV valve from
cylinder head (valve) cover. The valve should rattle
when shaken (Fig. 11).
Fig. 11
Shake
PCV Valve-Typical
Replace the PCV valve and retest the system if it
does not operate as described in the preceding tests.
Do not attempt to clean the old PCV valve.
(5) If the paper is not held against the opening in
cylinder head (valve) cover after new valve is in­ stalled, the PCV valve hose may be restricted and
must be replaced. The passage in the intake manifold
must also be checked and cleaned. To clean the intake manifold fitting, turn a 1/4
inch drill (by hand) through the fitting to dislodge
any solid particles. Blow out the fitting with shop air. If necessary, use a smaller drill to avoid remov­
ing any metal from the fitting.
CRANKCASE
BREATHER/FILTER-GAS POWERED

ENGINES
The crankcase breather/filter (Fig. 12) is located on
the cylinder head (valve) cover. It must be kept clean and lubricated. At the recommended interval, remove
the filter and wash it thoroughly in kerosene or sim­ ilar solvent. Lubricate or wet the filter by inverting
it and filling with SAE 30 engine oil. Filter must
then be thoroughly drained. More frequent service
may be necessary for vehicles operated extensively on short run, stop and go or extended engine idle ser­

vice.
The filter must be replaced at correct intervals. Re­
fer to Lubrication and Maintenance, Group 0 in this service manual. 8925-28
Fig. 12 Crankcase Breather/Filter—Gas Powered
Engines

25-10
EMISSION
CONTROL
SYSTEMS

EXHAUST
EMISSION
CONTROLS

INDEX

page

Air Inlet—5.9L Diesel
Engine
13
Exhaust
Gas Recirculation (EGR)
Systems
10

HEATED
INLET
AIR
SYSTEM

The air filter housing mounted-heated inlet air sys­
tem is no longer used on any Dodge Truck gas pow­ ered engine.

EXHAUST
GAS
RECIRCULATION
(EGR)
SYSTEMS
GENERAL INFORMATION The EGR system reduces oxides of nitrogen (NOx)
in the engine exhaust and helps prevent spark
knock. This is accomplished by allowing a predeter­
mined amount of hot exhaust gas to recirculate and
dilute the incoming fuel/air mixture. This dilution
reduces peak flame temperature during combustion.
The system consists of an intake manifold mounted
EGR valve (Fig. 1) and connecting hoses. The vac­
uum to the EGR is controlled by the electric EGR
transducer (EET) (Figs. 1 and 2). The EET is a dual
electric/vacuum function switch. It is controlled by
engine vacuum and the powertrain control module (PCM).
Fig. 1 EGR System—Gas Powered Engines
EGR OPERATION The electric exhaust gas recirculation transducer
(EET) is a back pressure transducer and an electric
vacuum solenoid combined into a single unit (Figs. 1 and 2). The vacuum solenoid portion of the EET re­
ceives its electrical signal from the powertrain con­
trol module (PCM). Using this signal, the solenoid regulates the vacuum flowing through to the trans­ ducer portion of the EET. The back pressure trans-
page

Heated
Inlet
Air
System
. 10

Oxygen
(02)
Sensor
13

ELECTRICAL
VACUUM

CONNECTION
SUPPLY
9125-34

Fig.
2 Electric EGR Transducer
(EET)—Gas

Powered
Engines
ducer measures the amount of exhaust gas back
pressure on the exhaust side of the EGR valve. It
then varies the strength of the vacuum signal ap­
plied to the EGR valve. The transducer uses this
back pressure signal to provide the correct amount of exhaust gas recirculation under all conditions.
The vacuum supply for the EGR valve is controlled
by the EET. The electrical solenoid portion of the EET is controlled by the powertrain control module (PCM). The PCM monitors engine coolant tempera­
ture and other operating conditions to determine
when EGR operation is desired. Refer to Open Loop/ Closed Loop Modes of Operation in Group 14, Fuel
Systems for a description of EGR solenoid operation
based on engine operating conditions.
If the electrical connector to the EET is dis­
connected or the electrical signal is lost, the
EGR valve will operate at all times. This results
in poor engine performance and reduced driveability
during certain operating conditions.
Vacuum flows between the solenoid portion of the
EET and the transducer portion of the EET. This
happens only when the solenoid is not electrically en­ ergized. The transducer is connected to the EGR
valve by a vacuum hose and a back pressure hose.
The transducer is controlled by exhaust back pres­ sure and is ported to the exhaust manifold through a
hose connecting it to the bottom of the EGR valve.
Vacuum will be supplied to the EGR valve and
EGR operation will begin when:

EMISSION
CONTROL
SYSTEMS
25 - 13

For electrical tests
of the EET and its
circuitry,
re­

fer
to the
appropriate Powertrain Diagnostic Proce­ dures service manual
for use of the DRB II
scan tool.
Refer
to the
Component Removal/Installation sec­
tion
of
this group
for EET
replacement procedures.

OXYGEN
(02)
SENSOR
For description, operation, diagnosis
and
removal/
installation procedures
of the 02
sensor, refer
to
Group
14,
Fuel Systems.

AIR
INLET—5.9L
DIESEL
ENGINE
The diesel engine
air
inlet system consists
of the:

•
Air
filter housing
• Filter element •
Air
filter housing-to-turbocharger inlet tube
•
Air
crossover tube •
Air
intake heaters Ambient
air
enters
the air
filter housing through
an opening
at the
bottom
of the
housing
(Fig. 3). Air

in
the
housing
is
filtered
by the air
filter element (Fig.
4)
before
it is
drawn into
the
turbocharger.
Fig.
4 Air Filter
Element—Diesel The turbocharger increases
the
amount
of air
flow
to
the
engine.
The
turbocharger allows
the
engine
to
use
a
higher air-to-fuel ratio. This results
in im­

proved emissions.
Air flows from
the
turbocharger into
the
inter-
cooler
(Fig. 5). Air
leaves
the
intercooler, passes
through
the air
intake heaters
and
enters
the
intake manifold.

TURBOCHARGER
TURBOCHARGER
TO INTERCOOLER

INTERCOOLER
J9114-238
Fig.
5
Intercooler—Diesel
AIR INTAKE HEATER-DIESEL ENGINE The
air
intake heater warms
the
intake
air
before
it enters
the
manifold.
If
intake manifold
air
temper­ ature
is
below
16°C
(60°F)
the
powertrain control
module
(PCM)
will energize
the
heaters through
the
air intake heater relays
for
start-up
and
initial
warm-up. Refer
to
Group
14,
Fuel Systems
for
addi­
tional information. The heater
is
located
on top of the
intake manifold,
below
the air
crossover tube
(Fig. 6).

CAUTION:
Do not
energize
the air
intake heater
re­
lays
more than once
per 15
minutes.
If the
relays
are cycled
and the key is
then turned
off,
wait
15
minutes
before turning
the key to the
ON
position.
The
15
minute period
is to
prevent damaging
the
engine.

AIR INTAKE HEATER RELAYS-DIESEL ENGINE The powertrain control module
(PCM)
operates
the

air intake heaters through
the air
intake heater
re­

lays
(Fig. 7). The
relays
are
energized before crank­
ing
if the
charge
air
temperature sensor input
to the

PCM indicates
air
temperature
is 16°C
(60°F)
or be-

•

EMISSION
CONTROL SYSTEMS
25 - 17
COMPONENT REMOVAL/INSTALLATION

INDEI

page

Air
Filter/Filter
Housing—Diesel Engines
17

Air
Filter/Filter
Housing—Gas Engines
17

Air
Injection
Pump
17

Air
Injection
Pump Relief Valve
18
Check
Valve—Air
Injection
Tube
18

Coolant Temperature
Sensor
. 18
EGR
Tube—Gas Powered Engines
19

EGR
Valve
19

AIR FILTER/FILTER HOUSING-GAS ENGINES
REMOVAL/INSTALLATION Remove crankcase breather/filter hose at side of air
filter housing. Remove wingnut (Fig. 1) and remove
housing from engine. Check condition of gasket at
throttle body and replace as necessary. To replace air filter element only: Remove wingnut
and air filter housing cover (Fig. 1). Clean inside of
housing before replacing filter. Housing removal is not necessary for filter replacement.
^
WING NUT

COVER
:

GASKET
| I
MOUNTING

STUD

Fig.
1 Air
Filter
Housing—Gas
Powered
Engines—Typical
page

Electric
EGR Transducer (EET)
20

EVAP
Canister
20

EVAP
Canister Purge Solenoid
20

Fuel Tank
Filler
Tube
Cap . 21

Oxygen
(02)
Sensor
21
Powertrain Control Module (PCM)
21

Pressure
Relief/Rollover Valve
21
If housing-to-throttle body mounting stud is being
installed, tighten to 10 N»m (90 in. lbs.) torque. In­ stall housing to engine and tighten wingnut to 1.5
N»m (15 in. lbs.) torque.

AIR FILTER/FILTER HOUSING-DIESEL ENGINES
REMO
VAL/INSTALLA
TION Remove the hose clamp at air filter housing (Fig.

2).
Remove mounting nuts and remove air filter
housing from vehicle.
To replace air filter element only: Remove hose clamp
and hose at air filter housing inlet tube. Remove three
wingnuts and air filter housing cover (Figs. 2 and 3). Clean inside of housing before replacing filter. Housing
removal is not necessary for filter replacement.
When installing a new air filter element, push el­
ement into cover. Be sure it is pushed into tabs in
back of filter housing. Install wing nuts.
If housing had been removed, install mounting
nuts and tighten to 10 N»m (95 in. lbs.) torque.

AIR INJECTION PUMP
REMOVAL (1) Remove the relief valve hose clamp (Fig. 4) and
remove hose at relief valve.
(2) Remove relief valve from air pump (two bolts)
(Fig. 4). (3) Loosen (but do not remove at this time) the
three air pump pulley mounting bolts (number 2—figure 4).
(4) Relax the automatic belt tensioner and remove
the engine accessory drive belt. Refer to Group 7, Cooling System. See Belt Removal/Installation.
(5) Remove the three air pump pulley bolts and re­
move pulley from pump.
(6) Remove the two air pump mounting bolts
(number
1—figure
4) and remove pump from mount­
ing bracket.

25
- 18
EMISSION
CONTROL
SYSTEMS

Fig. 2 Air Filter Housing—Diesel Fig. 3 Air Filter Element—Diesel INSTALLATION
(1) Install air injection pump and two bolts to
mounting bracket. Tighten bolts to 40 N*m (30 ft.
lbs.) torque. (2) Install pulley and three mounting bolts.
Tighten bolts to 11 N*m (105 in. lbs.) torque.
(3) Install drive belt. Refer to Group 7, Cooling
System. See Belt Removal/Installation.
(4) Clean the gasket mounting area on the air
pump and valve. (5) Install a new gasket (Fig. 4) (relief valve-to-
pump) and install relief valve to pump. Tighten bolts to 10 N*m (95 in. lbs.) torque.
(6) Install relief valve hose and hose clamp to re­
lief valve. •

RELIEF
VALVE
J9325-39

Fig. 4 Air Injection
Pump
and
Components

AIR
INJECTION PUMP RELIEF VALVE REMOVAL

(1) Remove the relief valve hose clamp (Fig. 4) and
remove hose at relief valve.
(2) Remove relief valve from air pump (two bolts)
(Fig. 4). Discard old gasket.

INSTALLATION (1)
Clean the gasket mounting area on the pump
and valve. (2) Install a new gasket (Fig. 4) (relief valve-to-
pump) and install relief valve to pump. Tighten bolts
to 10 N*m (95 in. lbs.) torque. (3) Install relief valve hose and hose clamp to re­
lief valve.

CHECK
VALVE—AIR INJECTION TUBE REMOVAL
(1) Remove the hose clamp at inlet side of valve.
(2) Remove hose from valve.
(3) Remove valve from catalyst tube (unscrew). To
prevent damage to catalyst tube, a backup
wrench must be used on tube.

INSTALLATION
(1) Install valve to catalyst tube. Tighten to 33
N«m (25 ft. lbs.) torque.
(2) Install hose and hose clamp to valve.

COOLANT TEMPERATURE SENSOR
For description, operation, diagnosis and removal/
installation procedures, refer to Group 14, Fuel Sys­

tems.

•

EMISSION
CONTROL SYSTEMS
25 - 19
EGR
VALVE

REMOVAL

The EGR valve and the electric EGR transducer
(EET) are serviced as one unit.
(1) Disconnect vacuum hose to EGR valve/trans­
ducer assembly. Note position of hoses on EGR valve
and transducer for easier installation.
(2) Remove EGR mounting bolts (Fig. 5).

Fig.
5 EGR
Valve
Mounting
Bolts

(3) Remove EGR valve and gasket. Discard old
gasket. Clean intake manifold mating surface and
check for cracks.

INSTALLATION
(1) Place new EGR gasket on intake manifold. (2) Install EGR valve. Tighten mounting bolts to
23 N*m (200 in. lbs.) torque. (3) Connect vacuum hose to valve/transducer as­
sembly.

EGR
TUBE-GAS POWERED ENGINES

REMOVAL
(1) Remove air filter housing.
(2) Remove the spark plug cable loom and plug ca­
bles from valve cover mounting stud at rear of right
valve cover. Position spark plug cables to top of valve cover.
(3) Disconnect two vacuum hoses at exhaust gas
recirculation (EGR) valve. (4) Remove 2 EGR valve mounting bolts (Fig. 5)
and remove EGR valve. Discard old gasket.
(5) Disconnect electrical connector at engine oil
pressure sending unit.
(6) To prevent damage to oil pressure sending unit,
a special tool, such as number C-4597 must be used
(Fig. 6). Remove sending unit from engine.
(7) Loosen EGR tube mounting nut at intake man­
ifold (Fig. 7).
Fig.
6 Oil
Pressure
Sending
Unit—Removal/Installation

Fig.
7 EGR Tube—Typical
(8) Remove EGR tube mounting bolts at exhaust
manifold (Fig. 7) and remove EGR tube.

INSTALLATION
(1) Clean the EGR tube and exhaust manifold (at
EGR tube mounting point) of any old gasket mate­

rial.
(2)
Install a new gasket to exhaust manifold end of
EGR tube. (3) Install EGR tube to both manifolds. Tighten
mounting nut at intake manifold. Tighten two
mounting bolts at exhaust manifold to 23 N»m (204 in. lbs.) torque.
(4) Coat the threads of the oil pressure sending
unit with thread sealant. Do not allow any of the
thread sealant to get into the sending unit opening
or the opening at the engine. Install sending unit to

25 - 20
EMISSION CONTROL SYSTEMS

• engine and tighten to 14 N*m (130 in. lbs.) torque.
Install electrical connector to sending unit.
(5) Clean the intake manifold and EGR valve of
any old gasket material.
(6) Install a new EGR valve gasket to intake man­
ifold. (7) Install EGR valve to intake manifold. Tighten
two mounting bolts to 23 N*m (200 in. lbs.) torque.
(8) Install vacuum lines to EGR valve.
(9) Install spark plug cable loom and plug cables to
valve cover mounting stud.
(10) Install air filter housing.

ELECTRIC EGR TRANSDUCER
(EET) The EGR valve and the EET are serviced as one
unit. Also refer to EGR valve removal/installation.

REMOVAL
(1) Remove air filter housing.
(2) Disconnect wiring connector at EET (Fig. 8). (3) Disconnect hoses at EET. Note position of hoses
for easier installation.
(4) Remove EET from engine.
INSTALLATION (1) Position EET to engine and connect hoses.
(2) Connect wiring connector. (3) Install air filter housing.

ELECTRICAL
CONNECTOR
TRANSDUCER
J9325-15

Fig.
8 Electric EGR Transducer (EET)—Typical

EVAP
CANISTER
The EVAP canister is mounted in the engine com­
partment on the right side wheel well (Fig. 9).

REMOVAL
(1) Remove fuel tubes/lines at EVAP canister.
Note location of tubes/lines before removal for easier
installation. (2) Remove mounting bolt at canister mounting
strap (Fig. 9).
(3) Remove canister and two-piece strap from
mounting bracket.
CANISTER

MOUNTING
STRAPS
CANISTER

MOUNTING
BRACKET RIGHT FRONT
INNER FENDER

MOUNTING
BOLT
EVAP
CANISTER
J9325-36

Fig.
9
EVAP
Canister Removal/Installation INSTALLATION
(1) Position canister to mounting bracket.
(2) Install canister and both mounting straps to
mounting bracket.
(3) Install canister bolt and tighten to 10 N*m (95
in. lbs.) torque.
(4) Install fuel tubes/lines to canister.

EVAP
CANISTER PURGE SOLENOID
REMOVAL
(1) Remove air filter housing.
(2) Disconnect wiring connector at solenoid (Fig.

10). BRACKET
MOUNTING

NUT
ELECTRICAL
CONNECTOR
CANISTER PURGE
SOLENOID/BRACKET VACUUM
CONNECTOR

J9214-50

Fig.
10
EVAP
Canister
Purge
Solenoid—
Typical

(3) Disconnect vacuum harness at solenoid (Fig.

10).

•
EMISSION CONTROL SYSTEMS 25 - 21 (4) Remove solenoid and its support bracket from
intake manifold (one bolt—5.2L/5.9L engine, one
nut—3.9L engine). (5) Remove EVAP canister purge solenoid from en­

gine.

INSTALLATION
(1) Install EVAP canister purge solenoid and its
mounting bracket to intake manifold.
(2) Connect vacuum harness and wiring connector.
(3) Install air filter housing.
FUEL TANK FILLER TUBE CAP If replacement of the fuel filler tube cap (Fig. 11) is
necessary, it must be replaced with an identical cap
to be sure of correct system operation.

CAUTION:
Remove
the
fuel
tank
filler
tube
cap to
relieve
fuel
tank
pressure.
The cap
must
be re­
moved
prior
to
disconnecting
any
fuel
system
com­

ponent
or
before
draining
the
fuel
tank.
PLASTIC

GASKET
RN348
Fig.
11
Fuel
Tank
Filler
Tube Cap—Typical
OXYGEN (02) SENSOR For description, operation, diagnosis and removal/
installation procedures of the 02 sensor, refer to Group 14, Fuel Systems. POWERTRAIN CONTROL MODULE (PCM)
For removal and installation procedures, refer to
Group 14, Fuel Systems.
PRESSURE RELIEF/ROLLOWER WALWE For removal and installation procedures, refer to
the Fuel Tank section of Group 14, Fuel Systems.