check engine DODGE TOWN AND COUNTRY 2001 Service Manual

ORVR
OPERATION
The emission control principle used in the ORVR sys-
tem is that the fuel flowing into the filler tube (appx. 1º
I.D.) creates an aspiration effect which draws air into
the fill tube (Fig. 6). During refueling, the fuel tank is
vented to the vapor canister to capture escaping vapors.
With air flowing into the filler tube, there are no fuel
vapors escaping to the atmosphere. Once the refueling
vapors are captured by the canister, the vehicle's com-
puter controlled purge system draws vapor out of the
canister for the engine to burn. The vapors flow is
metered by the purge solenoid so that there is no or
minimal impact on driveability or tailpipe emissions.
As fuel starts to flow through the fill tube, it opens
the normally closed check valve and enters the fuel
tank. Vapor or air is expelled from the tank through the
control valve to the vapor canister. Vapor is absorbed in
the canister until vapor flow in the lines stops, either
following shut-off or by having the fuel level in the tank
rise high enough to close the control valve. The controlvalve(Refer to 14 - FUEL SYSTEM/FUEL DELIVERY/
FUEL TANK - OPERATION) contains a float that rises
to seal the large diameter vent path to the canister. At
this point in the fueling of the vehicle, the tank pres-
sure increases, the check valve closes (preventing tank
fuel from spiting back at the operator), and fuel then
rises up the filler tube to shut-off the dispensing nozzle.
If the engine is shut-off while the On-Board diagnos-
tics test is running, low level tank pressure can be
trapped in the fuel tank and fuel can not be added to
the tank until the pressure is relieved. This is due to
the leak detection pump closing the vapor outlet from
the top of the tank and the one-way check valve not
allowing the tank to vent through the fill tube to atmo-
sphere. Therefore, when fuel is added, it will back-up in
the fill tube and shut off the dispensing nozzle. The
pressure can be eliminated in two ways: 1. Vehicle
purge must be activated and for a long enough period to
eliminate the pressure. 2. Removing the fuel cap and
allowing enough time for the system to vent thru the
recirulation tube.
Fig. 6 ORVR System Schematic
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 - CONTROL VALVE
RSEVAPORATIVE EMISSIONS25-15
ProCarManuals.com

DIAGNOSIS AND TESTING - VEHICLE DOES
NOT FILL
CONDITION POSSIBLE CAUSES CORRECTION
Pre-Mature Nozzle Shut-Off Defective fuel tank assembly
components.Fill tube improperly installed
(sump)
Fill tube hose pinched.
Check valve stuck shut.
Control valve stuck shut.
Defective vapor/vent components. Vent line from control valve to
canister pinched.
Vent line from canister to vent
filter pinched.
Canister vent valve failure
(requires double failure,
plugged to LDP and
atmosphere).
Leak detection pump failed
closed.
Leak detection pump filter
plugged.
On-Board diagnostics evaporative
system leak test just conducted.Canister vent valve vent
plugged to atmosphere.
engine still running when
attempting to fill (System
designed not to fill).
Defective fill nozzle. Try another nozzle.
Fuel Spits Out Of Filler
Tube.During fill. See Pre-Mature Shut-Off.
At conclusion of fill. Defective fuel handling
component. (Check valve stuck
open).
Defective vapor/vent handling
component.
Defective fill nozzle.
25 - 16 EVAPORATIVE EMISSIONSRS
ORVR (Continued)
ProCarManuals.com

A failed or malfunctioning EGR system can cause
engine spark knock, sags or hesitation, rough idle,
engine stalling and increased emissions.
REMOVAL - 2.4L
The EGR valve and Electrical EGR Transducer are
serviced as an assembly (Fig. 1).(1) Disconnect vacuum tube from electric EGR
transducer. Inspect vacuum tube for damage.
(2) Remove electrical connector from solenoid.
(3) Remove EGR tube bolts from EGR valve.
(4) Remove EGR valve from cylinder head adaptor.
(5) Clean gasket surface and discard old gasket.
Check for any signs of leakage or cracked surfaces.
Repair or replace as necessary.
REMOVAL - 3.3/3.8L
The EGR valve and Electrical EGR Transducer are
serviced as an assembly (Fig. 2).
(1) Disconnect vacuum tube from electric EGR
transducer. Inspect vacuum tube for damage.
(2) Remove electrical connector from solenoid.
(3) Remove EGR tube bolts from EGR valve.
(4) Remove EGR valve from cylinder head adaptor.
(5) Clean gasket surface and discard old gasket.
Check for any signs of leakage or cracked surfaces.
Repair or replace as necessary.
INSTALLATION - 2.4L
The EGR valve and Electrical EGR Transducer are
serviced as an assembly (Fig. 1).
(1) Assemble EGR valve with new gasket onto the
cylinder head adaptor.
(2) Loose assemble the bolts from EGR valve to
EGR tube.
(3) Loose assemble the bolts from EGR valve to
cylinder head.
(4) Tighten bolts from EGR valve to cylinder head
to 22.8 N´m (200625 in. lbs.) torque.
(5) Tighten bolts from EGR valve to EGR tube to
11.9 N´m (105620 in. lbs.) torque.
(6) Reconnect vacuum hose and electrical connec-
tor to electrical EGR transducer.
INSTALLATION - 3.3/3.8L
The EGR valve and Electrical EGR Transducer are
serviced as an assembly (Fig. 2).
(1) Loose assemble the bolts from EGR valve to
EGR tube.
(2) Loose assemble the bolts from EGR valve to
cylinder head adaptor.
(3) Tighten bolts from EGR valve to EGR tube to
11.9 N´m (105620 in. lbs.) torque.
(4) Tighten bolts from EGR valve to cylinder head
to 22.9 N´m (200625 in. lbs.) torque.
(5) Reconnect vacuum hose and electrical connec-
tor to electrical EGR transducer.
Fig. 3 EGR Valve and Transducer - Typical
1 - DIAPHRAGM
2 - PISTON
3 - SPRING
4 - EGR VALVE ASSEMBLY
5 - VACUUM MOTOR
6 - VACUUM MOTOR FITTING
7 - VACUUM OUTLET FITTING TO EGR VALVE
8 - EGR VALVE CONTROL ASSEMBLY
9 - ELECTRIC SOLENOID PORTION OF VALVE CONTROL
10 - VACUUM INLET FITTING FROM ENGINE
11 - BACK-PRESSURE HOSE
12 - TRANSDUCER PORTION OF VALVE CONTROL
13 - ELECTRICAL CONNECTION POINT
14 - EGR VALVE BACK-PRESSURE FITTING
15 - EXHAUST GAS INLET
16 - STEM PROTECTOR AND BUSHING
17 - BASE
18 - MOVEMENT INDICATOR
19 - POPPET VALVE
20 - SEAT
21 - EXHAUST GAS OUTLET
25 - 22 EXHAUST GAS RECIRCULATIONRS
VALVE (Continued)
ProCarManuals.com