Hot Idle Compensation: Description

This system is used only on GLC models. It supplies additional air to intake manifold under hot idle conditions in order to maintain smooth idle and reduce emissions. A bimetal valve in air cleaner opens passage from air cleaner to intake manifold. When this happens, this fresh air mixes with rich air/fuel mixture (caused by sustained idle) and creates better combustion. Valve opens above 152°F (67°C).