EGR Backpressure Transducer: Testing and Inspection
INSPECTION OF EGR VACUUM MODULATORCHECK EGR VACUUM MODULATOR OPERATION
(a) Disconnect the vacuum hoses from the ports of the EGR vacuum modulator.
(b) Block the port with your finger.
(c) Blow air into another port and check that the air passes through to the air filter side freely.
(d) Start the engine and maintain speed at 2,500 rpm.
(e) Repeat the above test. Check that there is a strong resistance to air flow.
(f) Reconnect the vacuum hoses to the proper locations.