EGR Backpressure Transducer: Testing and Inspection

Modulator Valve Check:

1. Remove valve.
2. Plug #3 port and attach vacuum pump to #1 port.
3. Blow into exhaust gas port. Operate vacuum pump and verify vacuum is held at #3 port.
4. Release exhaust gas port and verify vacuum released at #3 port.
5. If not as specified, replace modulator valve.