Tacoma Extra Cab 2WD V6-3.4L (5VZ-FE) (1998)
EGR Backpressure Transducer: Testing and Inspection
EGR VACUUM MODULATOR INSPECTION
1. DISCONNECT VACUUM HOSES FROM EGR VACUUM MODULATOR
Disconnect these vacuum hoses:
(1) Vacuum hose from R port
(2) Vacuum hose from Q port
(3) Vacuum hose from P port
2. INSPECT EGR VACUUM MODULATOR OPERATION
(a) Block ports P and R with your finger.
(b) Blow air into port Q and check that the air passes through to the air filter side freely.
(c) Start the engine and maintain speed at 3,500 rpm.
(d) Repeat the above test. Check that there is a strong resistance to air flow.
3. RECONNECT VACUUM HOSES TO EGR VACUUM MODULATOR
Connect these vacuum hoses:
(1) Vacuum hose to R port
(2) Vacuum hose to Q port
(3) Vacuum hose to P port