Checking the thermostatic air filter (Mazda Capella GC)

1. All engines are equipped with a thermostatic air filter, through which air is supplied to the carburetor from different places, depending on the engine temperature.

2. This check is a simple inspection. If access is limited, you will have to use a small mirror.

3. Open the hood and locate the spring-loaded flap inside the air cleaner assembly. It is located inside the metal air filter housing, which is shaped like a tube. Make sure the flexible air hose(s) are securely attached and not damaged.

4. If there is a flexible air duct attached to the end of the filter housing that goes to the radiator grille, disconnect it from the housing - this will allow you to see the spring-loaded flap inside the filter assembly.

5. The check is performed in cool weather and with a cold engine. When the engine starts, the spring-loaded filter flap should close. When the damper is closed, air cannot enter the filter through the end of the housing, so air is drawn into it through a flexible channel leading to the exhaust manifold.

6. Once the engine warms up to operating temperature, the filter flap should open. Depending on the ambient temperature, warming up can take 10-15 minutes. To speed things up, you can connect an air duct to the end of the filter housing and take the car for a short drive, then check to see if the filter flap is fully open (photo).