The S40/V50 PZEV (partial zero emission vehicle) model year (MY) 2007 has an upgraded hardware configuration for improved PZEV capability balanced with the best possible customer attributes.
The base engine is the Volvo naturally aspirated inline 5-cylinder that, together with new technology, achieves PZEV emission performance with maximum cost efficiency.
The engine out emissions were reduced by a newly-developed injection synchronization strategy during engine crank. The reduced number of engine revolutions during crank result in less hydrocarbon (HC) emissions from the cylinder pumping effect prior to the first cylinder combustion.
Thanks to the Volvo developed start strategy that during lean lambda operation generates an extreme temperature ramp in the front part of the catalyst in a very early phase after cold start, in combination with a new unique oxygen-sensor installation, catalyst control is started extremely early. Furthermore, with a new catalyst installation gas mixing has been enhanced. The result is a greatly improved robustness whilst achieving PZEV emission standards including 240,000 km endurance.