Exhaust Gas Recirculation System — Check (Opel Astra F)

Start the engine and bring it to normal operating temperature.

Stop the engine and remove the air box from the top of the fuel injection unit as previously described.

Connect an accurate tachometer to the engine according to the instructions in the instrument manufacturer's instructions.

Disconnect the vacuum hose from the EGR valve, then start the engine and record the idle speed.

Disconnect the vacuum hose from the valve, then apply vacuum to the valve using a hand vacuum pump. Once connected, the idle speed should drop by at least 100 rpm.

If the idle speed has not decreased as stated above, first check the vacuum hose of the valve for clogging or leakage. Clean the hose or replace it if necessary.

If the hose is in good condition and the defect remains, then there is a possibility that it is in the valve. In this case, clean the valve and, if necessary, replace it as described below.

Disconnect the tachometer, connect the vacuum hose and install the air box.