DODGE NEON 2000 Service Repair Manual

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 connec-
tor pins.
HIGH AND LOW LIMITS
OPERATION
The PCM compares input signal voltages from each
input device with established high and low limits forthe device. If the input voltage is not within limits
and other criteria are met, the PCM stores a diagnos-
tic trouble code in memory. Other diagnostic trouble
code criteria might include engine RPM limits or
input voltages from other sensors or switches that
must be present before verifying a diagnostic trouble
code condition.
LOAD VALUE
ENGINE IDLE/NEUTRAL 2500 RPM/NEUTRAL
2.0L 2% to 8% of Maximum Load 8% to 15% of Maximum Load
25 - 24 EMISSION CONTROL SYSTEMSPL
DESCRIPTION AND OPERATION (Continued)

EVAPORATIVE EMISSION CONTROLS
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
EVAPORATION CONTROL SYSTEM..........25
EVAP CANISTER.........................25
PROPORTIONAL PURGE SOLENOIDÐPCM
OUTPUT..............................25
LEAK DETECTION PUMP..................26
LEAK DETECTION PUMP PRESSURE
SWITCH..............................27
POSITIVE CRANKCASE VENTILATION (PCV)
SYSTEMS.............................28POSITIVE CRANKCASE VENTILATION VALVE. . . 28
VEHICLE EMISSION CONTROL
INFORMATION LABEL...................29
REMOVAL AND INSTALLATION
EVAP CANISTER.........................29
LEAK DETECTION PUMP..................30
PROPORTIONAL PURGE SOLENOID VALVE....30
DESCRIPTION AND OPERATION
EVAPORATION CONTROL SYSTEM
OPERATION
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 to an activated carbon
filled evaporative canister. The canister temporarily
holds the vapors. The Powertrain Control Module
(PCM) allows intake manifold vacuum to draw
vapors into the combustion chambers during certain
operating conditions.
All engines use a proportional purge solenoid sys-
tem. The PCM controls vapor flow by operating the
purge solenoid. Refer to Proportional Purge Solenoid
in this section.
NOTE: The evaporative system uses specially man-
ufactured hoses. If they need replacement, only use
fuel resistant hose. Also the hoses must be able to
pass an Ozone compliance test.
NOTE: For more information on Onboard Refueling
Vapor Recovery (ORVR), refer to the Fuel Delivery
section.
EVAP CANISTER
DESCRIPTION
The vacuum and vapor tubes connect to the top of
the canister (Fig. 1).
OPERATION
All vehicles use a, maintenance free, evaporative
(EVAP) canister. Fuel tank vapors vent into the can-
ister. The canister temporarily holds the fuel vapors
until intake manifold vacuum draws them into the
combustion chamber. The Powertrain Control Module
(PCM) purges the canister through the proportional
purge solenoid. The PCM purges the canister at pre-
determined intervals and engine conditions.
Purge Free Cells
Purge-free memory cells are used to identify the
fuel vapor content of the evaporative canister. Since
the evaporative canister is not purged 100% of the
time, the PCM stores information about the evapora-
tive canister's vapor content in a memory cell.
The purge-free cells are constructed similar to cer-
tain purge-normal cells. The purge-free cells can be
monitored by the DRB III Scan Tool. The only differ-
ence between the purge-free cells and normal adap-
tive cells is that in purge-free, the purge is
completely turned off. This gives the PCM the ability
to compare purge and purge-free operation.
PROPORTIONAL PURGE SOLENOIDÐPCM
OUTPUT
DESCRIPTION
OPERATION
All vehicles use a proportional purge solenoid. The
solenoid regulates the rate of vapor flow from the
EVAP canister to the throttle body. The PCM oper-
ates 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.
PLEMISSION CONTROL SYSTEMS 25 - 25

The proportional purge solenoid operates at a fre-
quency of 200 hz and is controlled by an engine con-
troller circuit that senses the current being applied
to the proportional purge solenoid (Fig. 2) and then
adjusts that current to achieve the desired purge
flow. The proportional purge solenoid controls the
purge rate of fuel vapors from the vapor canister and
fuel tank to the engine intake manifold.
LEAK DETECTION PUMP
DESCRIPTION
The leak detection pump is a device used to detect
a leak in the evaporative system.
The pump contains a 3 port solenoid, a pump that
contains a switch, a spring loaded canister vent valve
seal, 2 check valves and a spring/diaphragm.
OPERATION
Immediately after a cold start, when the engine
temperature is between 40ÉF and 86ÉF, the 3 port
solenoid is briefly energized. This initializes the pump
by drawing air into the pump cavity and also closes
the vent seal. During non-test test conditions, the
vent seal is held open by the pump diaphragm assem-
bly which pushes it open at the full travel position.
The vent seal will remain closed while the pump is
cycling. This is due to the operation of the 3 port sole-
noid which prevents the diaphragm assembly from
reaching full travel. After the brief initialization
period, the solenoid is de-energized, allowing atmo-
spheric pressure to enter the pump cavity. This per-
mits the spring to drive the diaphragm which forces
air out of the pump cavity and into the vent system.
When the solenoid is energized and de-energized, the
cycle is repeated creating flow in typical diaphragm
pump fashion. The pump is controlled in 2 modes:
1 ± FUEL CAP
2 ± RECIRCULATION TUBE
3 ± LIQUID SEPARATOR
4 ± PURGE
5 ± W/LDP
6 ± BREATHER ELEMENT
7 ± W/O LDP8 ± CANISTER
9 ± ROLLOVER VALVE
10 ± FUEL TANK
11 ± CHECK VALVE
12 ± LIQUID TRAP
13 ± CONTROL VALVE
ORVR System Schematic
25 - 26 EMISSION CONTROL SYSTEMSPL
DESCRIPTION AND OPERATION (Continued)

PUMP MODE:The pump is cycled at a fixed rate
to achieve a rapid pressure build in order to shorten
the overall test time.
TEST MODE:The solenoid is energized with a
fixed duration pulse. Subsequent fixed pulses occur
when the diaphragm reaches the switch closure
point.
The spring in the pump is set so that the system
will achieve an equalized pressure of about 7.5 inches
of water.
When the pump starts, the cycle rate is quite high.
As the system becomes pressurized, pump rate drops.
If there is no leak, the pump will quit. If there is a
leak, the test is terminated at the end of the test
mode.If there is no leak, the purge monitor is run. If the
cycle rate increases due to the flow through the
purge system, the test is passed and the diagnostic is
complete.
The canister vent valve will unseal the system
after completion of the test sequence as the pump
diaphragm assembly moves to the full travel position.
LEAK DETECTION PUMP PRESSURE SWITCH
OPERATION
The leak detection pump LDP assembly incorpo-
rates two primary functions: it detects a leak in the
evaporative system, and it seals the evaporative sys-
tem so that the required leak detection monitor test
can be run.
The primary components within the leak detection
pump assembly are: a three-port leak detection sole-
noid valve, a pump assembly that includes a spring
loaded diaphragm, a reed switch which is used to
monitor the pump diaphragm movement (position),
two check valves, and a spring loaded vent seal
valve.
The three-port LDP solenoid valve is used to
expose either engine vacuum or atmospheric pressure
to the top side of the leak detection pump diaphragm.
When the LDP solenoid valve is deenergized its
port (opening) to engine vacuum is blocked off. This
allows ambient air (atmospheric pressure) to enter
the top of the pump diaphragm. The spring load on
the diaphragm will push the diaphragm down, as
long as there is no pressure present in the rest of the
evaporative system. If there is sufficient evaporative
system pressure present, then the pump diaphragm
will stay in the ªupº position. If the evaporative sys-
tem pressure decays, then the pump diaphragm will
eventually fall. The rate of this decent is dependent
upon the size of the evaporative system leak (Large
or small).
When the LDP solenoid valve is energized the port
(opening) to atmosphere is blocked off. At the same
time, the port to engine vacuum is opened. Engine
vacuum replaces atmospheric pressure. When engine
vacuum is sufficient, it over comes the spring pres-
sure load on the pump diaphragm and causes the
diaphragm to rise to its ªupº position. The reed
switch will change state depending upon the position
of the pump diaphragm.
If the diaphragm is in the ªupº position the reed
switch will be in its ªopenº state. This means that
the 12 volt signal sense to the PCM is interrupted.
Zero volts is detected by the PCM. If the pump dia-
phragm is in the ªdownº position the reed switch will
be in its ªclosedº state. 12 volts is sent to the PCM
via the switch sense circuit.
Fig. 1 EVAP Canister
Fig. 2 Proportional Purge Solenoid
PLEMISSION CONTROL SYSTEMS 25 - 27
DESCRIPTION AND OPERATION (Continued)

The check valves are one-way valves. The first
check valve is used to draw outside air into the lower
chamber of the LDP (the space that is below the
pump diaphragm). The second check valve is used to
vent this outside air, which has become pressurized
from the fall of the pump diaphragm, into the evap-
orative system.
The spring loaded vent seal valve, inside the LDP
is used to seal off the evaporative system. When the
pump diaphragm is in the ªupº position the spring
pushes the vent seal valve closed. The vent seal valve
opens only when the pump diaphragm is in its ªfull
downº position. When the pump assembly is in its
pump mode the pump diaphragm is not allowed to
descend (fall) so far as to allow the vent seal valve to
open. This allows the leak detection pump to develop
the required pressure within the evaporative system
for system leak testing.
A pressure build up within the evaporative system
may cause pressure on the lower side of the LDP dia-
phragm. This will cause the LDP diaphragm to
remain in its ªupº position (stuck in the up position).
This condition can occur even when the solenoid
valve is deenergized. This condition can be caused by
previous cycling (pumping) of the LDP by the techni-
cian (dealer test). Another way that this condition is
created is immediately following the running of the
vehicle evaporative system monitor. In this case, the
PCM has not yet opened the proportional purge sole-
noid in order to vent the pressure that has been built
up in the evaporative system to the engine combus-
tion system. The technician will need to vent the
evaporative system pressure via the vehicle fuel filler
cap and its fuel filler secondary seal (if so equipped
in the fuel filler neck). This will allow the technician
to cycle the LDP and to watch switch state changes.
After passing the leak detection phase of the test,
system pressure is maintained until the purge sys-
tem is activated, in effect creating a leak. If the dia-
phragm falls (as is expected), causing the reed switch
to change state, then the diagnostic test is completed.
When of the evaporative system leak monitor
begins its various tests, a test is performed to deter-
mine that no part of the evaporative system is
blocked. In this test, the LDP is cycled (pumped) a
calibrated (few) number of times. Pressure should not
build up in the evaporative system. If pressure is
present, then LDP diaphragm is forced to stay in its
ªupº position. The reed switch now stays open and
the PCM senses this open (incorrect) state. The evap-
orative system monitor will fail the test because of a
detected obstruction within the system.
Possible causes:
²Open or shorted LDP switch sense circuit
²Leak Detection Pump switch failure²Open fused ignition switch output
²Restricted, disconnected, or blocked manifold
vacuum source
²Obstruction of hoses or lines
²PCM failure
POSITIVE CRANKCASE VENTILATION (PCV)
SYSTEMS
DESCRIPTION
OPERATION
Intake manifold vacuum removes crankcase vapors
and piston blow-by from the engine. The emissions
pass through the PCV valve into the intake manifold
where they become part of the calibrated air-fuel
mixture. They are burned and expelled with the
exhaust gases. The air cleaner supplies make up air
when the engine does not have enough vapor or
blow-by gases. In this system, fresh air does not
enter the crankcase.
POSITIVE CRANKCASE VENTILATION VALVE
OPERATION
The PCV valve contains a spring loaded plunger.
The plunger meters the amount of crankcase vapors
routed into the combustion chamber based on intake
manifold vacuum.
When the engine is not operating or during an
engine backfire, the spring forces the plunger back
against the seat. This prevents vapors from flowing
through the valve (Fig. 4).
When the engine is at idle or cruising, high mani-
fold vacuum is present. At these times manifold vac-
uum is able to completely compress the spring and
Fig. 3 PCV System
25 - 28 EMISSION CONTROL SYSTEMSPL
DESCRIPTION AND OPERATION (Continued)

pull the plunger to the top of the valve (Fig. 5). In
this position there is minimal vapor flow through the
valve.
During periods of moderate intake manifold vac-
uum the plunger is only pulled part way back from
the inlet. This results in maximum vapor flow
through the valve (Fig. 6).
VEHICLE EMISSION CONTROL INFORMATION
LABEL
DESCRIPTION
All models have a Vehicle Emission Control Infor-
mation (VECI) Label. DaimlerChrysler permanently
attaches the label in the engine compartment. It can-
not be removed without defacing information and
destroying the label.
The label contains the vehicle's emission specifica-
tions and vacuum hose routings. All hoses must be
connected and routed according to the label.
REMOVAL AND INSTALLATION
EVAP CANISTER
REMOVAL
(1) Disconnect the negative battery cable.
(2) Raise vehicle and support.
(3) Disconnect the hoses from the EVAP canister
(Fig. 7).
(4) Remove 1 nuts from the bracket of the EVAP
canister (Fig. 8).
(5) Remove EVAP canister from bracket.
Fig. 4 Engine Off or Engine BackfireÐNo Vapor
Flow
Fig. 5 High Intake Manifold VacuumÐMinimal Vapor
Flow
Fig. 6 Moderate Intake Manifold VacuumÐMaximum
Vapor Flow
Fig. 7 EVAP Canister
Fig. 8 EVAP Bracket and Bracket
PLEMISSION CONTROL SYSTEMS 25 - 29
DESCRIPTION AND OPERATION (Continued)

INSTALLATION
(1) Install EVAP canister to Bracket (Fig. 8).
(2) Install 2 nuts to EVAP canister and bracket
and tighten nuts to 6.7 N´m (60 in. lbs.).
(3) Connect hoses.
(4) Install EVAP canister and bracket to vehicle
and tighten nut 22.4 N´m (250 in. lbs.).
(5) Lower vehicle.
(6) Connect negative battery cable.
LEAK DETECTION PUMP
REMOVAL
(1) Raise and support vehicle on a hoist.
(2) Push locking tab on electrical connector to
unlock and remove connector.
(3) loosen the sway bar bracket to remove the
pump bracket.
(4) Remove pump and bracket as an assembly.
(5) Disconnect lines from LDP.
(6) Remove filter.
(7) Remove pump from bracket.
INSTALLATION
(1) Install pump to bracket and tighten bolts to 1.2
N´m (10.6 in. lbs.).
(2) Install filter and tighten to 2.8 N´m (25 in.
lbs.).
(3)Before installing hoses to LDP, make sure
they are not cracked or split. If a hose leaks, it
will cause the Check Engine Lamp to illumi-
nate.Connect lines to the LDP.
NOTE: The LDP bracket must be between the rail
and sway bar bracket.
(4) Install pump and bracket assembly to body and
tighten bolts to 5.0 N´m (45 in. lbs.).
(5) Install sway bar bracket bolt and tighten bolts
to 33.8 N´m (25 ft. lbs.).
(6) Install electrical connector to pump and push
locking tab to lock.
(7) Lower vehicle(8) Use the DRB scan tool, verify proper operation
of LDP.
PROPORTIONAL PURGE SOLENOID VALVE
The solenoid attaches to a bracket near the steer-
ing gear (Fig. 9). The solenoid will not operate unless
it is installed correctly.
REMOVAL
(1) Raise vehicle and support.
(2) Disconnect electrical connector from solenoid.
(3) Disconnect vacuum tubes from solenoid.
(4) Remove solenoid from bracket.
INSTALLATION
The top of the solenoid has TOP printed on it. The
solenoid will not operate unless it is installed cor-
rectly.
(1) Install solenoid on bracket.
(2) Connect vacuum tube to solenoid.
(3) Connect electrical connector to solenoid.
(4) Lower vehicle.
Fig. 9 Proportional Purge Solenoid Valve
25 - 30 EMISSION CONTROL SYSTEMSPL
REMOVAL AND INSTALLATION (Continued)

BODY
TABLE OF CONTENTS
page page
PAINT................................... 1
STATIONARY GLASS........................ 4
SEATS ................................... 8BODY COMPONENTS...................... 12
SPECIFICATIONS......................... 60
PAINT
TABLE OF CONTENTS
page page
DESCRIPTION AND OPERATION
PAINT CODE.............................1
BASE COAT/CLEAR COAT FINISH.............1
WET SANDING, BUFFING, AND POLISHING.....1PAINTED SURFACE TOUCH-UP..............1
SPECIFICATIONS
AFTERMARKET PAINT REPAIR PRODUCTS.....2
DESCRIPTION AND OPERATION
PAINT CODE
A paint code is provided on the body code plate
located in the engine compartment. Refer to the
Introduction section at the front of this manual for
body code plate description. The paint and trim codes
are also included on the Vehicle Safety Label located
on the driver's door end frame.
BASE COAT/CLEAR COAT FINISH
On most vehicles a two-part paint application (base
coat/clear coat) is used. Color paint that is applied to
primer is called base coat. The clear coat protects the
base coat from ultraviolet light and provides a dura-
ble high-gloss finish.
CAUTION: Do not use abrasive chemicals or com-
pounds on painted surfaces. Damage to finish can
result.
Do not use harsh alkaline based cleaning sol-
vents on painted surfaces. Damage to finish or
color can result.
WET SANDING, BUFFING, AND POLISHING
Minor acid etching, orange peel, or smudging in
clear coat or single-stage finishes can be reduced
with light wet sanding, hand buffing, and polishing.
If the finish has been wet sanded in the past, itcannot be repeated. Wet sanding operation
should be performed by a trained automotive
paint technician.
CAUTION: Do not remove clear coat finish, if
equipped. Base coat paint must retain clear coat for
durability.
PAINTED SURFACE TOUCH-UP
When a painted metal surface has been scratched
or chipped, it should be touched-up as soon as possi-
ble to avoid corrosion. For best results, use Mopart
Scratch Filler/Primer, Touch-Up Paints and Clear Top
Coat. Refer to Introduction group of this manual for
Body Code Plate information.
CAUTION: USE A OSHA APPROVED BREATHING
FILTER WHEN SPRAYING PAINT OR SOLVENTS IN
A CONFINED AREA. PERSONAL INJURY CAN
RESULT.
TOUCH-UP PROCEDURE
(1) Scrape loose paint and corrosion from inside
scratch or chip.
(2) Clean affected area with MopartTar/Road Oil
Remover, and allow to dry.
(3) Fill the inside of the scratch or chip with a coat
of filler/primer. Do not overlap primer onto good sur-
PLBODY 23 - 1

face finish. The applicator brush should be wet
enough to puddle-fill the defect without running. Do
not stroke brush applicator on body surface. Allow
the filler/primer to dry hard.
(4) Cover the filler/primer with color touch-up
paint. Do not overlap touch-up color onto the original
color coat around the scratch or chip. Butt the new
color to the original color, if possible. Do not stroke
applicator brush on body surface. Allow touch-up
paint to dry hard.
(5) On vehicles without clear coat, the touch-up
color can be lightly wet sanded (1500 grit) and pol-
ished with rubbing compound.(6) On vehicles with clear coat, apply clear top coat
to touch-up paint with the same technique as
described in Step 4. Allow clear top coat to dry hard.
If desired, Step 5 can be performed on clear top coat.
CAUTION: AVOID PROLONGED SKIN CONTACT
WITH PETROLEUM OR ALCOHOL ± BASED CLEAN-
ING SOLVENTS. PERSONAL INJURY CAN RESULT.
SPECIFICATIONS
AFTERMARKET PAINT REPAIR PRODUCTS
EXTERIOR COLORS
EXTERIOR
COLORCHRY
CODE*PPG DUPONTS-W
M-S **A-N/S ** S-H ** ICI **
Black Clear
CoatDX8 9700 F0206 34858 CHA85:DX8 73328 TC60B
Bright White
Clear CoatGW7 4037 B8833 37298 CHA88:GW7 11751 TA45B
Bright Silver
Metallic Clear
CoatWS2 5464 F7999 56150 CHA99:WS2 74611 KDP8B
Cinnamon
Glaze Metallic
Clear CoatVLB 5313 B9824 54469 CHA98:VLB 80758 HMT2B
Deep
Amethyst
Pearl CoatTCN5246 B9751 52566 CHA97:TCN 54755 FNE4B
Deep
Cranberry
Pearl CoatVMT5359 B9842 54119 CHA98:VMT 33686 GJX2B
Flame Red
Clear CoatPR4 4679 B9326 46916 CHA93:PR4 30116 2NNGB
Forest Green
Pearl CoatSG8 5065 B9609 51062 CHA95:SG8 61633 7MR8B
Patriot Blue
Pearl CoatWB75512 F7991 56683 CHA99:WB7 56580 LEC6B
Salsa Red
Pearl CoatWE5 5442 F7998 56147 CHA99:WE5 34462 5WS8B
*BASF, Glasurit, and Standox use the DaimlerChrysler paint code.
** S-W = Sherwin Williams, M-S = Martin Senour,
A-N/S = Akzo Nobel/Sikkens, S-H = Spies Hecker and ICI = Autocolor
23 - 2 BODYPL
DESCRIPTION AND OPERATION (Continued)

INTERIOR COLORS
INTERIOR
COLORCHRY
CODE *PPG DUPONTS-W
M-S **A-N/S ** S-H ** ICI**
Agate AZ9856
C9208 45994 CHALAZI 75016 7WC8
2-1461
Taupe WL528653
C9881 54420 CHAWL5I 81650 KXE6
2-1652
PLBODY 23 - 3
SPECIFICATIONS (Continued)