EGR Valve: Testing and Inspection

EXHAUST GAS RECIRCULATION (EGR) VALVE, CHECKING:

Special Tools, Testers And Auxiliary Items:

^ US 8012 Hand vacuum pump

Test Conditions:

^ Vacuum lines and hose connections tree of leaks.

^ Vacuum lines not blocked or kinked.

^ Engine oil temperature at least 50 °C

Test Sequence:

Vehicles up to 07.96:





- Disconnect vacuum hose -arrow- from EGR valve.

Vehicles from 08.96:





- Pull vacuum hose -arrow- off EGR valve N18 -1-.

Continued for all vehicles:

- Connect hand vacuum pump to valve using extension hose.

- Start engine and let idle.

- Operate hand vacuum pump.

^ Idle speed behavior must noticeably deteriorate.

If the idling characteristics do not deteriorate:

- Remove the EGR valve.

- Operate vacuum pump.

^ valve must open.

- Release vacuum again:

^ valve must close again.

- Check whether EGR system is blocked.