EGR Venturi Vacuum Amplifier
Idle must be set to specifications, engine must be at normal operating temperature and manifold vacuum must be adequate for this test.
1. Connect a vacuum gauge hose at EGR valve. The gauge may read as high as 2 inches Hg at idle.
2. Disconnect venturi hose at carburetor and increase engine speed to 2000 RPM (3000 on 2300 cc engines).
3. Connect venturi hose. Gauge should read 4 inches Hg.
4. Return engine to idle. Gauge should return to initial reading.
5. If operation is not as described previously, replace VVA.