Owner's Manual

2) Check the vacuum connection to the EGR valve

for obstructions.

3) Connect the pump between the EGR valve and

the carburetor or vacuum source. Start the engine

and run it at idle until it reaches operating

temperature (195°F approx.). Check for vacuum

at 3000 RPM; it should be 5" Hg minimum.

4) If no vacuum is available in step 3, check for it

between the EGR thermal vacuum switch (TVS) and

the carburetor. If the vacuum is available there,

replace the TVS.

5) If the vacuum supply between the EGR and the

carburetor is adequate, connect the pump to the

EGR valve inlet. Depress the valve diaphragm and

apply approximately 10" Hg vacuum to the EGR.

Release the diaphragm and record the time it takes

for the diaphragm to return to its seated position.

6) If it takes less than 20 seconds for the valve to

seat, replace the valve.

GM POSITIVE BACKPRESSURE EGR TEST

1) Follow steps 1 through 4 of the ported vacuum

and negative back-pressure EGR test.

2) Remove the EGR valve from the engine.

Connect the pump to the EGR vacuum inlet and

apply 10" Hg of vacuum. The valve should not

open. If it does, replace the valve.

3) Continue the test by keeping the vacuum applied

and shooting a low-pressure stream of air into the

valve’s exhaust inlet. The valve should now open.

If it does not, replace the valve.

EXHAUST GAS RECIRCULATION (EGR)

FIGURE 8: CHRYSLER VENTURI VACUUM-CONTROL EGR SYSTEM

To Starter Relay

Manifold Vacuum

To Ignition

Vacuum Amplifier

EGR Delay

Solenoid

EGR Valve

EGR Delay

Timer

CCEGR Temperature Valve

Coolant Control Engine Vacuum Switch