3-Way Solenoid Valve (TWSV)
- Disconnect hoses connecting TWSV to EGR valve and EGR modulator. Connect test hoses to TWSV. See Fig 1 . Blow into test hose No. 1, checking that air escapes from test hose No. 2.
- Disconnect TWSV electrical connector and connect 12-volt battery to connector terminals. With battery connected, blow into test hose No. 1, checking that air escapes from TWSV filter and not test hose No. 2. If TWSV does not operate properly, replace with a new unit. Reconnect hoses and electrical connector.