Checking the air thermostat of the 2E3 carburetor (Opel Vectra A)

The air thermostat controls the supply of warm or cold air depending on the engine load and the temperature of the incoming air. For this purpose, a vacuum control device is located in the air intake of the air filter. A temperature-controlled valve is located in the air filter housing.

The results of a thermostat malfunction are:

• unstable engine operation at idle speed during warming up;
• unstable engine operation in transient modes;
• increased fuel consumption.

Disconnect the transparent tube from the air filter vacuum control valve and check the operation of the warm air flap 2 (see above fig.C4541), drawing air in through the tube with your mouth. The flap should close and open. If this does not happen, check the vacuum device 1 adjustment flap for ease of movement or replace the valve.

(Article posted on a web portal: opelbook)