Checking the exhaust gas recirculation valve (Opel Vectra A)

The C16NZ and C18NZ engines have a vacuum-controlled EGR valve located between the engine and the throttle body.

Examination

Remove the air filter.

Start the engine.

Grasp the diaphragm from below through the hole in the valve body with two fingers.

Press the accelerator rod (increase the number of revolutions). In this case, the diaphragm should move upward.

At idle, press the diaphragm upwards. The number of revolutions should decrease significantly.

If the diaphragm does not move when the "gas" is increased and, accordingly, the number of revolutions does not decrease, remove and clean the valve, replace it if necessary.