Remove the cylinder head cover and remove the spark plugs.
Turn, if necessary, the crankshaft behind the flange of the camshaft pulley.
Adjust the gap between the eccentric and the end of the valve stem by first loosening the rocker nut.
After adjustment, tighten the rocker nut with a special flanged wrench 11 1 150 and a torque wrench.
Clearances in the valve drive mechanism
The normal gap between the rocker eccentric and the end of the valve stem, measured with a feeler gauge on a cold engine, is 0.25 mm for the intake and exhaust valves.