Integral Backpressure Transducer Valve
- Disconnect vacuum line to EGR valve and plug. Connect vacuum pump to valve. Start engine and idle. Apply 6 in. Hg vacuum to valve. Vacuum should bleed off and valve should not operate.
- If vacuum holds and valve opens, replace valve. With engine at idle, there should be no vacuum to valve. If so, check vacuum hose routing. With engine cold, there should be no vacuum to valve. If so, check TVS or PVS and replace as required.
- With engine warm, there should be vacuum to valve at 3000 RPM for 2.3L engines, and kickdown RPM on all other engines. If not, check vacuum lines from EGR to source.
- Into end of tailpipe, clamp a plug about 1/16" less in diameter than I.D. of tailpipe. A drive socket with drive hole covered may be used. Idle engine and apply vacuum gradually. Valve stem/diaphragm should move smoothly and engine idle should roughen.
- Apply 6 in. Hg vacuum to the EGR valve and hold. Vacuum should not drop more than 1 in. Hg in 30 seconds. If valve test is okay but engine does not idle rough in test, clean valve passages. If problem persists, replace valve.