Two-stroke engines of this sort, with crankcase scavenging and lubricating oil provided during fuel intake, burn their lubricating oil by design and produce smoky tailpipe emissions. However, two-stroke engines were also to be found in cars like the Western German Auto Union 1000 that ended production in 1963, and the Swedish Saab 96 that changed to four-stroke in 1967. The lack of development funds in East Germany forced the continued use of a two-stroke engine in the Trabant, thus causing this vehicle to become obsolescent in the 1960s and extremely obsolete by the 1980s.