The PSA Group sells a variety of diesel automobile engines with the HDi (high-pressure direct injection) designation. Earlier versions were exclusive to Peugeot and Citroën. In 1998, PSA entered into a joint venture with the Ford Motor Company to produce a range of new diesel engines. The joint venture makes identical engines which are fitted to a variety of vehicles from a range of car manufacturers. The engines are assembled in production plants in the cities of Trémery and Douvrin for PSA in France, at the Ford Dagenham plant in the UK, and Volvo Engine Plant in Skövde Sweden when Volvo was still under Ford ownership.