Check the valve clearance.
If necessary, adjust the valve clearance by replacing the tappets.
Other information:
Components
1. Cylinder head cover
2. Fuel pump bracket gasket
3. Cylinder head cover gasket
4. Positive Crankcase Ventilation (PCV) valve
5. Fuel pump bracket
6. Camshaft bearing cap
7. Camshaft front bearing cap
8. Intake camshaft
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This is used to select the outside (fresh) air position or recirculated air position.
To change the air intake control position, push the control button.
Outside (fresh) air position
With the outside (fresh) air position selected, air enters the vehicle from outside
and is heated or cooled ...