Abstract: A method for application in conjunction with an exhaust gas post-treatment system for metering an ammonia-releasing reducing agent into the exhaust gas stream of an internal combustion engine installed in a motor vehicle and operated with excess air. A control unit meters the quantity of reducing agent as a function of a stored model and during the operation of the internal combustion engine varies the metered quantity during certain operating phases and compares the change in the measured value of at least one NOx sensor installed downstream of the SCR catalyst with an expected value.

Abstract: Rocker arm arrangement of an internal combustion engine has a bearing journal with a central axis and an outside circumferential surface running in the central bore of a rocker arm lined with a bearing shell. The bearing journal has a first transverse oil channel leading to at least one outlet at the running surface underneath the central axis. The bearing shell has an outer shell surface and an inner shell surface. The inner shell surface has a circumferentially extending internal groove, both ends of which terminate underneath the central axis, this groove extending to the outlet of the first oil channel when the rocker arm is in its base position. The outer shell surface has at least one circumferentially extending external groove, which extends as far as an inlet of a second oil channel passing through the rocker arm. At least one through-opening connects the internal groove and the external groove.