2001 DODGE RAM intake

(M)Malfunction Indicator Lamp (MIL) illuminated during engine operation if this DTC was recorded
(depending if required by CARB and/or EPA). MIL is displayed as an engine icon on instrument panel.
(G)Generator lamp illuminated
Generic Scan
Tool P-CodeDRB Scan Tool Display Brief Description of DTC
P1195 (M) 1/1 O2 Sensor Slow During Catalyst
MonitorA slow switching oxygen sensor has been detected in
bank 1/1 during catalyst monitor test. (Also see SCI DTC
$66) (was P0133)
P1196 (M) 2/1 O2 Sensor Slow During Catalyst
MonitorA slow switching oxygen sensor has been detected in
bank 2/1 during catalyst monitor test. (Also see SCI DTC
$7A) (was P0153)
P1197 1/2 O2 Sensor Slow During Catalyst
MonitorA slow switching oxygen sensor has been detected in
bank 1/2 during catalyst monitor test. (Also see SCI DTC
$68) (was P0139)
P1198 Radiator Temperature Sensor Volts
Too HighRadiator coolant temperature sensor input above the
maximum acceptable voltage.
P1199 Radiator Temperature Sensor Volts
Too LowRadiator coolant temperature sensor input below the
minimum acceptable voltage.
P1281 Engine is Cold Too Long Engine coolant temperature remains below normal
operating temperatures during vehicle travel (Thermostat).
P1282 Fuel Pump Relay Control Circuit An open or shorted condition detected in the fuel pump
relay control circuit.
P1283 Idle Select Signal Invalid ECM or fuel injection pump module internal fault condition
detected.
P1284 (M) Fuel Injection Pump Battery Voltage
Out-Of-RangeFuel injection pump module internal fault condition
detected. Engine power will be derated.
P1285 (M) Fuel Injection Pump Controller
Always OnFuel injection pump module relay circuit failure detected.
Engine power will be derated.
P1286 Accelerator Position Sensor (APPS)
Supply Voltage Too HighHigh voltage detected at APPS.
P1287 Fuel Injection Pump Controller
Supply Voltage LowECM or fuel injection pump module internal fault condition
detected. Engine power will be derated.
P1288 Intake Manifold Short Runner
Solenoid CircuitAn open or shorted condition detected in the short runner
tuning valve circuit.
P1289 Manifold Tune Valve Solenoid Circuit An open or shorted condition detected in the manifold
tuning valve solenoid control circuit.
P1290 CNG Fuel System Pressure Too
HighCompressed natural gas system pressure above normal
operating range.
P1291 No Temp Rise Seen From Intake
HeatersEnergizing Heated Air Intake does not change intake air
temperature sensor an acceptable amount.
P1291 (M) No Temperature Rise Seen From
Intake Air HeatersProblem detected in intake manifold air heating system.
P1292 CNG Pressure Sensor Voltage Too
HighCompressed natural gas pressure sensor reading above
acceptable voltage.
P1293 CNG Pressure Sensor Voltage Too
LowCompressed natural gas pressure sensor reading below
acceptable voltage.
P1294 (M) Target Idle Not Reached Target RPM not achieved during drive idle condition.
Possible vacuum leak or IAC (AIS) lost steps.
25 - 10 EMISSIONS CONTROLBR/BE
EMISSIONS CONTROL (Continued)

DESCRIPTION - TRIP DEFINITION
The term ªTripº has different meanings depending
on what the circumstances are. If the MIL (Malfunc-
tion Indicator Lamp) is OFF, a Trip is defined as
when the Oxygen Sensor Monitor and the Catalyst
Monitor have been completed in the same drive cycle.
When any Emission DTC is set, the MIL on the
dash is turned ON. When the MIL is ON, it takes 3
good trips to turn the MIL OFF. In this case, it
depends on what type of DTC is set to know what a
ªTripº is.
For the Fuel Monitor or Mis-Fire Monitor (contin-
uous monitor), the vehicle must be operated in the
ªSimilar Condition Windowº for a specified amount of
time to be considered a Good Trip.
If a Non-Contiuous OBDII Monitor fails twice in a
row and turns ON the MIL, re-running that monitor
which previously failed, on the next start-up and
passing the monitor, is considered to be a Good Trip.
These will include the following:
²Oxygen Sensor
²Catalyst Monitor
²Purge Flow Monitor
²Leak Detection Pump Monitor (if equipped)
²EGR Monitor (if equipped)
²Oxygen Sensor Heater Monitor
If any other Emission DTC is set (not an OBDII
Monitor), a Good Trip is considered to be when the
Oxygen Sensor Monitor and Catalyst Monitor have
been completed; or 2 Minutes of engine run time if
the Oxygen Sensor Monitor or Catalyst Monitor have
been stopped from running.
It can take up to 2 Failures in a row to turn on the
MIL. After the MIL is ON, it takes 3 Good Trips to
turn the MIL OFF. After the MIL is OFF, the PCM
will self-erase the DTC after 40 Warm-up cycles. A
Warm-up cycle is counted when the ECT (Engine
Coolant Temperature Sensor) has crossed 160ÉF and
has risen by at least 40ÉF since the engine has been
started.
DESCRIPTION - COMPONENT MONITORS -
GAS ENGINES
There are several components that will affect vehi-
cle emissions if they malfunction. If one of these com-
ponents malfunctions the Malfunction Indicator
Lamp (MIL) will illuminate.
Some of the component monitors are checking for
proper operation of the part. Electrically operated
components now have input (rationality) and output
(functionality) checks. Previously, a component like
the Throttle Position sensor (TPS) was checked by
the PCM for an open or shorted circuit. If one of
these conditions occurred, a DTC was set. Now there
is a check to ensure that the component is working.
This is done by watching for a TPS indication of agreater or lesser throttle opening than MAP and
engine rpm indicate. In the case of the TPS, if engine
vacuum is high and engine rpm is 1600 or greater,
and the TPS indicates a large throttle opening, a
DTC will be set. The same applies to low vacuum if
the TPS indicates a small throttle opening.
All open/short circuit checks, or any component
that has an associated limp-in, will set a fault after 1
trip with the malfunction present. Components with-
out an associated limp-in will take two trips to illu-
minate the MIL.
DESCRIPTION - COMPONENT MONITORS -
DIESEL ENGINES
There are several electrical components that will
affect vehicle emissions if they malfunction. If one of
these components is malfunctioning, a Diagnostic
Trouble Code (DTC) will be set by either the Power-
train Control Module (PCM) or the Engine Control
Module (ECM). The Malfunction Indicator Lamp
(MIL) will then be illuminated when the engine is
running.
These electrically operated components have input
(rationality) and output (functionality) checks. A
check is done by one or more components to check
the operation of another component.
Example:The Intake Manifold Air Temperature
(IAT) sensor is used to monitor intake manifold air
temperature over a period of time after a cold start.
If the temperature has not risen to a certain specifi-
cation during a specified time, a Diagnostic Trouble
Code (DTC) will be set for a problem in the manifold
air heater system.
All open/short circuit checks, or any component
that has an associated limp-in will set a DTC and
trigger the MIL after 1 trip with the malfunction
present. Components without an associated limp-in
will take two trips to illuminate the MIL.
OPERATION - GAS ENGINES
The Powertrain Control Module (PCM) monitors
many different circuits in the fuel injection, ignition,
emission and engine systems. If the PCM senses a
problem with a monitored circuit often enough to
indicate an actual problem, it stores a Diagnostic
Trouble Code (DTC) in the PCM's memory. If the
problem is repaired or ceases to exist, the PCM can-
cels the code after 40 warm-up cycles. Diagnostic
trouble codes that affect vehicle emissions illuminate
the Malfunction Indicator Lamp (MIL). The MIL is
displayed as an engine icon (graphic) on the instru-
ment panel. Refer to Malfunction Indicator Lamp in
this section.
Certain criteria must be met before the PCM
stores a DTC in memory. The criteria may be a spe-
25 - 18 EMISSIONS CONTROLBR/BE
EMISSIONS CONTROL (Continued)

FUEL PRESSURE
The fuel pressure regulator controls fuel system
pressure. The PCM cannot detect 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 condition causing the
PCM to store an oxygen sensor or fuel system diag-
nostic 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 is in 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 generated as a result of this condition. The mod-
ule 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 storediagnostic trouble codes as a result of spread connec-
tor pins.
OPERATION - NON-MONITORED CIRCUITS -
DIESEL
The PCM and/or the ECM will not monitor certain
malfunctioning circuits or components that could
cause driveability problems. Also, a Diagnostic Trou-
ble Code (DTC) might not be stored for these mal-
functions. However, problems with these circuits or
components may cause the PCM/ECM to store DTC's
for other circuits or components.EXAMPLES:A cyl-
inder with low compression will not set a DTC
directly, but may cause an engine misfire. This in
turn may cause the ECM to set a DTC for an engine
misfire. Or, a dirty or plugged air filter will not set a
DTC directly, but may cause lack of turbocharger
boost. This in turn may cause the ECM to set a DTC
for a boost pressure malfunction.
FUEL PRESSURE
Primary fuel pressure from the fuel tank to the
fuel injection pump is supplied by the low-pressure
fuel transfer pump. High-pressure to the fuel injec-
tors is supplied by the fuel injection pump. The ECM
cannot detect actual fuel pressure, a clogged fuel fil-
ter, clogged fuel screen, or a pinched fuel supply or
return line. However, a DTC may be set due to an
engine misfire.
CYLINDER COMPRESSION
The ECM cannot detect uneven, low, or high
engine cylinder compression. However, these could
result in a possible misfire which may set a DTC.
EXHAUST SYSTEM
The ECM cannot detect a plugged, restricted or
leaking exhaust system. However, DTC's may be set
for engine misfire, high intake manifold temperature,
high engine coolant temperature, turbocharger over-
boost or turbocharger underboost.
FUEL INJECTOR MECHANICAL MALFUNCTIONS
The ECM 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 possible
misfire which may set a DTC.
EXCESSIVE OIL CONSUMPTION
The ECM cannot determine excessive oil consump-
tion. However, if excess oil consumption is high
enough, it could result in a possible engine misfire
which may set a DTC.
BR/BEEMISSIONS CONTROL 25 - 23
EMISSIONS CONTROL (Continued)

AIR FLOW
The ECM cannot detect a clogged, restricted or
dirty air filter element, or a restriction in the air
inlet system. However, these could result in a possi-
ble misfire which may set a DTC.
AIR PRESSURE LEAKS
The ECM cannot detect leaks or restrictions in the
air intake system. However, these could cause the
ECM to store a Manifold Air Pressure (MAP) sensor
DTC (boost pressure problem detected).PCM/ECM SYSTEM GROUNDS
The PCM/ECM cannot directly determine poor sys-
tem grounds. However, one or more DTC's may be
generated as a result of poor grounds.
PCM/ECM CONNECTOR ENGAGEMENT
The PCM/ECM may not be able to determine
spread, damaged or corroded connector pins. How-
ever, it might store DTC's as a result of spread con-
nector pins (circuits that are open).
25 - 24 EMISSIONS CONTROLBR/BE
EMISSIONS CONTROL (Continued)

OPERATION - AIR INJECTION SYSTEM
The air injection system adds a controlled amount
of air to the exhaust gases aiding oxidation of hydro-
carbons and carbon monoxide in the exhaust stream.
The system does not interfere with the ability of the
EGR system (if used) to control nitrous oxide (NOx)
emissions.
5.9L HDC ENGINE:Air is drawn into the pump
through a rubber tube that is connected to a fitting
on the air cleaner housing (Fig. 2).
8.0L V-10 ENGINE:Air is drawn into the pump
through a rubber tube that is connected to a fitting
on the air injection pump filter housing (Fig. 3). Air
is drawn into the filter housing from the front of the
vehicle with rubber tube. This tube is used as asilencer to help prevent air intake noise at the open-
ing to the pump filter housing. An air filter is located
within the air pump filter housing (Fig. 3).
Air is then compressed by the air injector pump. It
is expelled from the pump and routed into a rubber
tube where it reaches the air pressure relief valve
(Fig. 1). Pressure relief holes in the relief valve will
prevent excess downstream pressure. If excess down-
stream pressure occurs at the relief valve, it will be
vented into the atmosphere.
Air is then routed (Fig. 1) from the relief valve,
through a tube, down to a9Y9connector, through the
two one-way check valves and injected at both of the
catalytic convertors (referred to as downstream).
The two one-way check valves (Fig. 1) protect the
hoses, air pump and injection tubes from hot exhaust
gases backing up into the system. Air is allowed to
flow through these valves in one direction only
(towards the catalytic convertors).
Downstream air flow assists the oxidation process
in the catalyst, but does not interfere with EGR oper-
ation (if EGR system is used).
Fig. 2 Air Inlet for Air PumpÐ5.9L HDC Engine
1 - AIR FILTER HOUSING
2 - AIR INLET TUBE
3 - INLET AIR FITTING
4 - AIR INJECTION PUMP
5 - OUTLET AIR FITTING
Fig. 3 Air Inlet and Air Pump Air
1 - INJECTION PUMP AIR FILTER HOUSING
2 - R. F. INNER FENDER
3 - FILTER HOUSING MOUNTING NUT
4 - PRESSURE RELIEF VALVE
5 - HOSE CLAMPS
6 - AIR INJECTION PUMP
7 - AIR INLET REDUCER
8 - LID
BR/BEAIR INJECTION 25 - 27
AIR INJECTION (Continued)

EVAPORATIVE EMISSIONS
TABLE OF CONTENTS
page page
EVAPORATIVE EMISSIONS
DESCRIPTION...........................31
SPECIFICATIONS........................31
CCV HOSE
DESCRIPTION...........................32
OPERATION.............................32
CRANKCASE VENT HOSE
DESCRIPTION...........................32
EVAP/PURGE SOLENOID
DESCRIPTION...........................32
REMOVAL..............................32
INSTALLATION...........................32
FUEL FILLER CAP
DESCRIPTION...........................33
OPERATION.............................33
REMOVAL..............................33
LEAK DETECTION PUMP
DESCRIPTION...........................33REMOVAL..............................34
INSTALLATION...........................34
PCV FILTER
DESCRIPTION...........................35
P C V VA LV E
DESCRIPTION...........................35
OPERATION.............................35
DIAGNOSIS AND TESTING.................36
PCV VALVE TEST - 3.9/5.2/5.9L ENGINE.....36
VACUUM LINES
DIAGNOSIS AND TESTING.................37
VACUUM SCHEMATICS..................37
VAPOR CANISTER
DESCRIPTION...........................37
OPERATION.............................37
REMOVAL..............................37
INSTALLATION...........................38
EVAPORATIVE EMISSIONS
DESCRIPTION - EVAP SYSTEM
The evaporation control system prevents the emis-
sion of fuel tank vapors into the atmosphere. When
fuel evaporates in the fuel tank, the vapors pass
through vent hoses or tubes into the two charcoal
filled evaporative canisters. The canisters tempo-
rarily hold the vapors. The Powertrain Control Mod-
ule (PCM) allows intake manifold vacuum to draw
vapors into the combustion chambers during certain
operating conditions.
All 3.9L/5.2L/5.9L/8.0L gasoline powered engines
use a duty cycle purge system. The PCM controlsvapor 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 evaporative system. This pump is used as part of
OBD II requirements. Refer to Leak Detection Pump
in this group 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 - EVAP SYSTEM
DESCRIPTION N´m Ft. Lbs. In. Lbs.
EVAP Canister Mounting Nuts 9 80
Leak Detection Pump Mounting Screws 1 11
Leak Detection Pump Filter Mounting
Bolt765
BR/BEEVAPORATIVE EMISSIONS 25 - 31

CCV HOSE
DESCRIPTION - 8.0L
The 8.0L V-10 engine is equipped with a Crankcase
Ventilation (CCV) system. The CCV system performs
the same function as a conventional PCV system, but
does not use a vacuum controlled valve (PCV valve).
A molded vacuum tube connects manifold vacuum
to the top of the right cylinder head (valve) cover.
The vacuum tube connects to a fixed orifice fitting
(Fig. 1) of a calibrated size 2.6 mm (0.10 inches).
OPERATION - 8.0L
A molded vacuum tube connects manifold vacuum
to the top of the right cylinder head (valve) cover.
The vacuum tube connects to a fixed orifice fitting
(Fig. 1) of a calibrated size 2.6 mm (0.10 inches). The
fitting meters the amount of crankcase vapors drawn
out of the engine.The fixed orifice fitting is grey
in color.A similar fitting (but does not contain a
fixed orifice) is used on the left cylinder head (valve)
cover. This fitting is black in color. Do not inter-
change these two fittings.When the engine is operating, fresh air enters the
engine and mixes with crankcase vapors. Manifold
vacuum draws the vapor/air mixture through the
fixed orifice and into the intake manifold. The vapors
are then consumed during engine combustion.
CRANKCASE VENT HOSE
OPERATION
The crankcase breather/filter is no longer used
with the 3.9L, 5.2L or 5.9L engine.
EVAP/PURGE SOLENOID
DESCRIPTION
All 3.9L/5.2L/5.9L/8.0L gasoline powered engines
use a duty cycle EVAP canister purge solenoid. The
solenoid regulates the rate of vapor flow from the
EVAP canister to the throttle body. The Powertrain
Control Module (PCM) operates the solenoid.
During the cold start warm-up period and the hot
start time delay, the PCM does not energize the sole-
noid. When de-energized, no vapors are purged. The
PCM de-energizes the solenoid during open loop oper-
ation.
The engine enters closed loop operation after it
reaches a specified temperature and the time delay
ends. During closed loop operation, the PCM ener-
gizes and de-energizes the solenoid 5 or 10 times per
second, depending upon operating conditions. The
PCM varies the vapor flow rate by changing solenoid
pulse width. Pulse width is the amount of time the
solenoid energizes. The PCM adjusts solenoid pulse
width based on engine operating condition.
REMOVAL
The duty cycle solenoid is attached to a bracket
mounted to the right inner fender (Fig. 2).
(1) Disconnect electrical wiring connector at sole-
noid (Fig. 2).
(2) Disconnect vacuum harness at solenoid.
(3) Remove solenoid from support bracket.
INSTALLATION
(1) Install solenoid assembly to support bracket.
(2) Connect vacuum harness.
(3) Connect wiring connector.
Fig. 1 Fixed Orifice FittingÐ8.0L V-10 EngineÐ
Typical
1 - VACUUM TUBE
2 - FIXED ORIFICE FITTING
3 - COIL PACKS
4 - ORIFICE FITTING HOSE CONNECTIONS
25 - 32 EVAPORATIVE EMISSIONSBR/BE

REMOVAL
The LDP and LDP filter are attached to a bracket
mounted to the right-inner fender (Fig. 2). The LDP
and LDP filter are replaced (serviced) as one unit.
(1) Carefully remove hose at LDP filter.
(2) Remove LDP filter mounting bolt and remove
from vehicle.
(3) Carefully remove vapor/vacuum lines at LDP.
(4) Disconnect electrical connector at LDP (Fig. 2).
(5) Remove LDP mounting screws and remove
LDP from vehicle.
INSTALLATION
The LDP and LDP filter are attached to a bracket
mounted to the right-inner fender (Fig. 2). The LDP
and LDP filter are replaced (serviced) as one unit.(1) Install LDP to mounting bracket. Tighten
screws to 1 N´m (11 in. lbs.) torque.
(2) Install LDP filter to mounting bracket. Tighten
bolt to 7 N´m (65 in. lbs.) torque.
(3) Carefully install vapor/vacuum lines to LDP,
and install hose to LDP filter.The vapor/vacuum
lines and hoses must be firmly connected.
Check the vapor/vacuum lines at the LDP, LDP
filter and EVAP canister purge solenoid for
damage or leaks. If a leak is present, a Diagnos-
tic Trouble Code (DTC) may be set.
(4) Connect electrical connector to LDP.
Fig. 3 Evaporative System Monitor SchematicÐTypical
1 - DUTY CYCLE PURGE SOLENOID (DCPS) DRIVER
2 - POWERTRAIN CONTROL MODULE (PCM)
3 - 3-PORT SOLENOID DRIVER
4 - REMOTE FILTER
5 - COMBINED CANISTER VENT VALVE & LEAK DETECTION
PUMP
6 - CANISTER7 - TANK ROLLOVER VALVE & VAPOR FLOW CONTROL
ORIFICE
8 - INTAKE MANIFOLD
9 - THROTTLE BODY
10 - DCPS
11 - SWITCH SIGNAL INPUT TO THE PCM
12 - ENGINE VACUUM LINE
25 - 34 EVAPORATIVE EMISSIONSBR/BE
LEAK DETECTION PUMP (Continued)