Chrysler 1997 Stratus Convertible RHD Service Manual page 1191

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DIAGNOSIS AND TESTING (Continued)
EGR SYSTEM TEST
WARNING: APPLY
BLOCK WHEELS BEFORE TESTING THE EGR SYS-
TEM.
(1) Check the condition of all EGR system hoses
and tubes for leaks, cracks, kinks and hardening of
rubber hoses. Repair and correct these conditions
before performing any tests.
(2) Be sure the hoses at both the EGR valve and
EGR valve control are connected to the proper fit-
tings (Fig. 5).
(3) Be sure the electrical connector is firmly con-
nected at the valve control.
(4) To check EGR system operation, connect the
DRB scan tool to the 16–way data link connector.
The data link connector is located on the lower edge
of the instrument panel near the steering column.
Refer to the appropriate Powertrain Diagnostic Pro-
cedures service manual for operation of the DRB STEM PROTECTOR DIA- P HRAGM PISTON MOVEMENT BASE INDICATOR AND BUSHING EGR SPRING ASSEMBLY EXHAUST VALVE EGR VACUUMMOTOR VALVE GAS EXHAUST INLET MOTOR FITTING VACUUM VACUUM FITTING GAS SURE FITTING OUT-
scan tool when diagnosing the EGR system.
(5) After checking the system with the DRB scan
tool, proceed to the following EGR Valve Leakage and
EGR Valve Control Tests and repair as necessary.
Fig. 5 EGR Value and EGR Value —Typical
PARKING BRAKE AND/OR
POPPET BACK-PRES- LET EGR TO TROL ASSEMBLY SEAT VALVE OUTLET VALVE VALVE CONNECTION ELECTRICAL EGR CON- POINT TION TRANSDUCER POR- TION OF VALVE SOLENOID POR- ELECTRIC VACUUM INLET FITTING OF CONTROL CONTROL VALVE FROM ENGINE
EGR GAS FLOW TEST
Use the following test procedure to determine if
exhaust gas is flowing through the EGR valve. It can
also be used to determine if the EGR tube is plugged,
or the system passages in the intake or exhaust man-
ifolds are plugged.
This is not to be used as a complete test of the
EGR system.
The engine must be started, running and warmed
to operating temperature for this test.
(1) All engines are equipped with two fittings
located on the EGR valve (Fig. 6). The upper fitting
(located on the vacuum motor) supplies engine vac-
uum to a diaphragm within the EGR valve for valve
operation. The lower fitting (located on the base of
the EGR valve) is used to supply exhaust back-pres-
sure to the EGR valve control.
BACK- PRESSURE HOSE
(2) Disconnect the rubber hose at the vacuum
motor fitting (Fig. 6) on the top of the EGR valve
vacuum motor.
(3) Connect a hand-held vacuum pump to this fit-
ting.
(4) Start the engine.
(5) Slowly apply 5 inches of vacuum to the fitting
on the EGR valve motor.
(6) While applying vacuum, a minimum of 3 inches
of vacuum, and with the engine running at idle
speed, the idle speed should drop or the engine may
even stall, if the vacuum is applied quickly. This is
indicating that exhaust gas is flowing through the
EGR tube between the intake and exhaust manifolds.
EMISSION CONTROL SYSTEMS
Fig. 6 Typical EGR Valve
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