fuel filter DODGE RAM SRT-10 2006 Service Manual Online

OPERATION
High-pressure fuel is supplied from the injection pump, through a high-pressure fuel line, into a fuel rail, through
high-pressure lines, through steel connectors and into the solenoid actuated fuel injector. The ECM actuates the
solenoid causing the needle valve to rise and fuel flows through the spray holes in the nozzle tip into the combus-
tion chamber.
Each fuel injector is connected to the fuel rail by a high-pressure fuel line and a steel connector. This steel con-
nector is positioned into the cylinder head and sealed with an O-ring. The connector is retained in the cylinder head
by a nut (fitting) that is threaded into the cylinder head.
The torquing force of this threaded nut (fitting) provides a sealing pressure between the fuel line connector and the
fuel injector.Retaining nut torque is very critical.If the nut (fitting) is under torqued, the mating surfaces will not
seal and a high-pressure fuel leak will result. If the fitting is over torqued, the connector and injector will deform and
also cause a high-pressure fuel leak. This leak will be inside the cylinderhead and will not be visible. The result will
be a possible fuel injector miss-fire and low power, or a no-start condition.
The fuel injectors use hole type nozzles. High-pressure flows into the side of the injector, the ECM activates the
solenoid causing the injector needle to lift and fuel to be injected. The clearances in the nozzle bore are extremely
small and any dirt or contaminants will cause the injector to stick. Because of this, it is very important to do a
thorough cleaning of any lines before opening up any fuel system component. Always cover or cap any open fuel
connections before a fuel system repair is performed.
Each fuel injector connector tube contains an edge filter that is designedto break up small contaminants before
entering the fuel injector.The edge filters are not a substitute for proper cleaning and covering of allfuel
system components during repair.
The bottom of each fuel injector is sealed to the cylinder head with a1.5mmthick copper shim (gasket). The correct
thickness shim must always be re-installed after removing an injector.
Fuel pressure in the injector circuit decreases after injection. The injector needle valve is immediately closed and
fuel flow into the combustion chamber is stopped. Exhaust gases are prevented from entering the injector nozzle by
the needle valve.
REMOVAL
CAUTION: Refer to Cleaning Fuel System Parts.
Six individual, solenoid actuated high-pressure fuel
injectors (7) are used. The injectors are vertically
mounted into a bored hole in the top of the cylinder
head. This bored hole is located between the intake/
exhaust valves. High-pressure connectors, mounted
into the side of the cylinder head, connect each fuel
injector to each high-pressure fuel line.
1. Disconnect both negative battery cables from both batteries. Cover andisolate ends of cables.
2. Remove vanity cover.
3. Remove breather assembly and tubes.

3. Lift 2 rubber covers (3) to gain access to 2 positive
(+) cable nuts.
4. Remove cable nut (6) (Fig #. ) and remove cable
from stud.
5. Remove wiring harness clips.
6. Remove engine oil dipstick tube bracket from air
inlet connection and fuel filter housing.
7. Remove four housing mounting bolts (1) and
remove heater element assembly.

Engine RPM— A live reading of engine RPM to aid the user in accessing the Similar Conditions Window.
Adaptive Memory Factor— The PCM utilizes both Short Term Compensation and Long Term Adaptive to
calculate the Adaptive Memory Factor for total fuel correction.
Upstream O2S Volts— A live reading of the Oxygen Sensor to indicate its performance. For example, stuck
lean, stuck rich, etc.
SCW Time in Window (Similar Conditions Window Time in Window)—Atimer used by the PCM that
indicates that, after all Similar Conditions have been met, if there has been enough good engine running time
in the SCW without failure detected. This timer is used to increment a Good Trip.
Fuel System Good Trip Counter—ATripCounterusedtoturnOFFtheMILforFuelSystemDTCs.To
increment a Fuel System Good Trip, the engine must be in the Similar Conditions Window, Adaptive Memory
Factor must be less than calibrated threshold and the Adaptive Memory Factor must stay below that threshold
for a calibrated amount of time.
Test Done This Trip— Indicates that the monitor has already been run and completed during the current trip.
MISFIRE
Same Misfire Warm-Up State— Indicates if the misfire occurred when the engine was warmed up above
160° F (71.1°C).
In Similar Misfire Window— An indicator that ’Absolute MAP When Misfire Occurred’ and ’RPM When Mis-
fire Occurred’ are all in the same range when the failure occurred. Indicated by switching from ’NO’ to ’YES’.
Absolute MAP When Misfire Occurred— The stored MAP reading at the time of failure. Informs the user at
what engine load the failure occurred.
Absolute MAP— A live reading of engine load to aid the user in accessing the Similar Conditions Window.
RPM When Misfire Occurred— The stored RPM reading at the time of failure. Informs the user at what
engine RPM the failure occurred.
Engine RPM— A live reading of engine RPM to aid the user in accessing the Similar Conditions Window.
Adaptive Memory Factor— The PCM utilizes both Short Term Compensation and Long Term Adaptive to
calculate the Adaptive Memory Factor for total fuel correction.
200 Rev Counter— Counts 0–100 720 degree cycles.
SCW Cat 200 Rev Counter— Counts when in similar conditions.
SCW FTP 1000 Rev Counter— Counts 0–4 when in similar conditions.
Misfire Good Trip Counter— Counts up to three to turn OFF the MIL.
Misfire Data— Data collected during test.
Test Done This Trip— Indicates YES when the test is done.
NON-MONITORED CIRCUITS
The PCM does not monitor the following circuits, systems and conditions that could have malfunctions causing
driveability problems. The PCM might not store diagnostic trouble codes for these conditions. However, problems
with these systems may cause the PCM to store diagnostic trouble codes for other systems or components.EXAM-
PLE:a fuel pressure problem will not register a fault directly, but could causea rich/lean condition or misfire. This
could cause the PCM to store an oxygen sensor or misfire diagnostic troublecode
FUEL PRESSURE
The fuel pressure regulator controls fuel system pressure. The PCM cannotdetect a clogged fuel pump inlet filter,
clogged in-line fuel filter, or a pinched fuel supply or return line. However, these could result in a rich or lean con-
dition causing the PCM to store an oxygen sensor or fuel system diagnostic trouble code.
SECONDARY IGNITION CIRCUIT
The PCM cannot detect an inoperative ignition coil, fouled or worn spark plugs, ignition cross firing, or open spark
plug cables.
CYLINDER COMPRESSION
The PCM cannot detect uneven, low, or high engine cylinder compression.

EXHAUST SYSTEM
The PCM cannot detect a plugged, restricted or leaking exhaust system, although it may set a fuel system fault.
FUEL INJECTOR MECHANICAL MALFUNCTIONS
The PCM cannot determine if a fuel injector is clogged, the needle is sticking or if the wrong injector is installed.
However, these could result in a rich or lean condition causing the PCM to store a diagnostic trouble code for either
misfire, an oxygen sensor, or the fuel system.
EXCESSIVE OIL CONSUMPTION
Although the PCM monitors engine exhaust oxygen content when the system isin closed loop, it cannot determine
excessive oil consumption.
THROTTLE BODY AIR FLOW
The PCM cannot detect a clogged or restricted air cleaner inlet or filter element.
VACUUM ASSIST
The PCM cannot detect leaks or restrictions in the vacuum circuits of vacuum assisted engine control system
devices. However, these could cause the PCM to store a MAP sensor diagnostic trouble code and cause a high idle
condition.
PCM SYSTEM GROUND
The PCM cannot determine a poor system ground. However, one or more diagnostic trouble codes may be gener-
ated as a result of this condition. The module should be mounted to the body at all times, also during diagnostic.
PCM CONNECTOR ENGAGEMENT
The PCM may not be able to determine spread or damaged connector pins. However, it might store diagnostic
trouble codes as a result of spread connector pins.

EVAPORATIVE EMISSIONS
DESCRIPTION - EVAP SYSTEM
The evaporation control system prevents the emission of fuel tank vapors into the atmosphere. When fuel evapo-
rates in the fuel tank, the vapors pass through vent hoses or tubes into the two charcoal filled evaporative canisters.
The canisters temporarily hold the vapors. The Powertrain Control Module(PCM) allows intake manifold vacuum to
draw vapors into the combustion chambers during certain operating conditions.
All gasoline powered engines use a duty cycle purge system. The PCM controls vapor flow by operating the duty
cycle EVAP purge solenoid. Refer to Duty Cycle EVAP Canister Purge Solenoid for additional information.
When equipped with certain emissions packages, a Leak Detection Pump (LDP) will be used as part of the evap-
orative system. This pump is used as a part of OBD II requirements. Refer to Leak Detection Pump for additional
information. Other emissions packages will use a Natural Vacuum Leak Detection (NVLD) system in place of the
LDP. Refer to NVLD for additional information.
NOTE: The hoses used in this system are specially manufactured. If replacement becomes necessary, it is
important to use only fuel resistant hose.
SPECIFICATIONS
TORQUE
DESCRIPTION Nꞏm Ft. Lbs. In. Lbs.
EVAP Canister Mounting
Nuts11 -95
EVAP Canister Mounting
Bracket-to-Frame Bolts14 10125
Leak Detection Pump
Mounting Bolts11 - 9 5
Breathers (PCV system) 12 - 106
Leak Detection Pump
Filter Mounting Bolt11 - 9 5

PUMP-LEAK DETECTION
DESCRIPTION
Vehicles equipped with JTEC engine control modules use a leak detection pump. Vehicles equipped with NGC
engine control modules use an NVLD pump. Refer to Natural Vacuum - Leak Detection (NVLD) for additional infor-
mation.
The evaporative emission system is designed to prevent the escape of fuel vapors from the fuel system. Leaks in
the system, even small ones, can allow fuel vapors to escape into the atmosphere. Government regulations require
onboard testing to make sure that the evaporative (EVAP) system is functioning properly. The leak detection system
tests for EVAP system leaks and blockage. It also performs self-diagnostics. During self-diagnostics, the Powertrain
Control Module (PCM) first checks the Leak Detection Pump (LDP) for electrical and mechanical faults. If the first
checks pass, the PCM then uses the LDP to seal the vent valve and pump air intothe system to pressurize it. If a
leak is present, the PCM will continue pumping the LDP to replace the air that leaks out. The PCM determines the
size of the leak based on how fast/long it must pump the LDP as it tries to maintain pressure in the system.
EVAP LEAK DETECTION SYSTEM
COMPONENTS
Service Port: Used with special tools like the Miller
Evaporative Emissions Leak Detector (EELD) to test
for leaks in the system.
EVAP Purge Solenoid: The PCM uses the EVAP
purge solenoid to control purging of excess fuel
vapors stored in the EVAP canister. It remains closed
during leak testing to prevent loss of pressure.
EVAP Canister: The EVAP canister stores fuel vapors
from the fuel tank for purging.
EVAP Purge Orifice: Limits purge volume.
EVAP System Air Filter: Provides air to the LDP for
pressurizing the system. It filters out dirt while allowing
a vent to atmosphere for the EVAP system.
OPERATION
The main purpose of the LDP is to pressurize the fuel system for leak checking. It closes the EVAP system vent to
atmospheric pressure so the system can be pressurized for leak testing. The diaphragm is powered by engine vac-
uum. It pumps air into the EVAP system to develop a pressure of about 7.5
H2O (1/4) psi. A reed switch in the LDP
allows the PCM to monitor the position of the LDP diaphragm. The PCM uses thereed switch input to monitor how
fast the LDP is pumping air into the EVAP system. This allows detection of leaks and blockage. The LDP assembly
consists of several parts. The solenoid is controlled by the PCM, and it connects the upper pump cavity to either
engine vacuum or atmospheric pressure. A vent valve closes the EVAP systemto atmosphere, sealing the system
during leak testing. The pump section of the LDP consists of a diaphragm that moves up and down to bring air in
through the air filter and inlet check valve, and pump it out through an outlet check valve into the EVAP system. The
diaphragm is pulled up by engine vacuum, and pushed down by spring pressure, as the LDP solenoid turns on and
off. The LDP also has a magnetic reed switch to signal diaphragm position tothe PCM. When the diaphragm is
down, the switch is closed, which sends a 12 V (system voltage) signal to thePCM. When the diaphragm is up, the
switch is open, and there is no voltage sent to the PCM. This allows the PCM tomonitor LDP pumping action as it
turns the LDP solenoid on and off.

REMOVAL
The Leak Detection Pump (LDP) (4) and LDP filter are attached to the front ofthe EVAP canister mounting bracket.
This is located near the front of the fuel tank. The LDP and LDP filter are replaced (serviced) as one unit.
1. Raise and support vehicle.
2. Certain models, equipped with a certain fuel tank size, may require the removal of the fuel tank skid plate and/or
the transfer case skid plate to gain access to the leak pump. Remove necessary skid plates.
3. Carefully remove hose at LDP filter.
4. Remove LDP filter mounting bolt and remove from vehicle.
5. Carefully remove vapor/vacuum lines at LDP.
6. Disconnect electrical connector at LDP.
7. Remove LDP mounting bolt and remove LDP from vehicle.

PUMP-NATURAL VAC LEAK DETECTION
DESCRIPTION
Vehicles equipped with an NGC Powertrain Control Module (PCM) use a Natural Vacuum Leak Detection (NVLD)
pump and system. Vehicles equipped with a JTEC PCM use an LDP (Leak Detection Pump). Refer to Leak Detec-
tion Pump (LDP) for additional information.
The NVLD pump is located in the same area as the leak detection pump. Refer toNVLD Removal / Installation for
additional information.
OPERATION
The Natural Vacuum Leak Detection (NVLD) system is the next generation evaporative leak detection system that
will first be used on vehicles equipped with the Next Generation Controller (NGC). This new system replaces the
leak detection pump as the method of evaporative system leak detection. This is to detect a leak equivalent to a
0.020
(0.5 mm) hole. This system has the capability to detect holes of this size very dependably.
The basic leak detection theory employed with NVLD is the
Gas Law. This is to say that the pressure in a sealed
vessel will change if the temperature of the gas in the vessel changes. The vessel will only see this effect if it is
indeed sealed. Even small leaks will allow the pressure in the vessel to come to equilibrium with the ambient pres-
sure. In addition to the detection of very small leaks, this system has the capability of detecting medium as well as
large evaporative system leaks.
A vent valve seals the canister vent during engine off conditions. If the vapor system has a leak of less than the
failure threshold, the evaporativesystem will be pulled into a vacuum, either due to the cool down from operating
temperature or diurnal ambient temperature cycling. The diurnal effect is considered one of the primary contributors
to the leak determination by this diagnostic. When the vacuum in the systemexceeds about 1
H2O (0.25 KPA), a
vacuum switch closes. The switch closure sends a signal to the NGC. The NGC,via appropriate logic strategies,
utilizes the switch signal, or lack thereof, to make a determination of whether a leak is present.
The NVLD device is designed with a normally open vacuum switch, a normally closed solenoid, and a seal, which
is actuated by both the solenoid and a diaphragm. The NVLD is located on the atmospheric vent side of the can-
ister. The NVLD assembly may be mounted on top of the canister outlet, or in-line between the canister and atmo-
spheric vent filter. The normally open vacuum switch will close with about1
H2O (0.25 KPA) vacuum in the
evaporative system. The diaphragm actuates the switch. This is above the opening point of the fuel inlet check valve
in the fill tube so cap off leaks can be detected. Submerged fill systems must have recirculation lines that do not
have the in-line normally closed check valve that protects the system fromfailednozzleliquidingestion,inorderto
detect cap off conditions.
The normally closed valve in the NVLD is intended to maintain the seal on theevaporative system during the engine
off condition. If vacuum in the evaporative system exceeds 3
to 6H2O (0.75 to 1.5 KPA), the valve will be pulled
off the seat, opening the seal. This will protect the system from excessivevacuum as well as allowing sufficient
purge flow in the event that the solenoid was to become inoperative.
The solenoid actuates the valve to unseal the canister vent while the engine is running. It also will be used to close
the vent during the medium and large leak tests and during the purge flow check. This solenoid requires an initial
1.5 amps of current to pull the valveopen, but after 100 mili-seconds, willbedutycycleddowntoanaverageof
about 150 mA for the remainder of the drive cycle.
Another feature in the device is a diaphragm that will open the seal in the NVLD with pressure in the evaporative
system. The device will
blow offat about 0.5H2O (0.12 KPA) pressure to permit the venting of vapors during
refueling. An added benefit to this is that it will also allow the tank to
breatheduring increasing temperatures, thus
limiting the pressure in the tank to this low level. This is beneficial because the induced vacuum during a subse-
quent declining temperature will achieve the switch closed (pass threshold) sooner than if the tank had to decay
from a built up pressure.
The device itself has 3 wires: Switch sense, solenoid driver and ground. Italso includes a resistor to protect the
switch from a short to battery or a short to ground. The NGC utilizes a high-side driver to energize and duty-cycle
the solenoid.

If Equipped With Vertically Mounted EVAP Canisters
The NVLD pump (4) is located at the front of fuel tank.
1. Snap NVLD pump (1) to EVAP canister until tab (2)
engages.
2. Connect electrical connector to NVLD pump.
3. Carefully install vapor/vacuum lines to NVLD pump.
The vapor/vacuum lines and hoses must be
firmly connected. Check the vapor/vacuum
lines at the NVLD pump, filter and EVAP canis-
ter purge solenoid for damage or leaks. If a leak
is present, a Diagnostic Trouble Code (DTC)
may be set.
4. If equipped, install skid plate(s).

3. Remove fuel tubes/lines (1) at each EVAP canister.
Note location of tubes/lines before removal for eas-
ier installation. Remove bolts (6).
4. Remove nut (1) and remove NVLD filter (2).