The second-generation trucks arrived for the 1994 model year. All of the special models (the Syclone, Typhoon, and Sonoma GT) were discontinued, but the changes to the pickup brought it in line with its major competitor the Ford Ranger. The Iron Duke 4-cylinder and 2.8 L 60° V6 engines were retired, the 4.3 L Vortec V6 was enhanced, and a new 2.2 L 4-cylinder engine (which had been introduced in 1990 on various front-wheel drive GM compact and mid-size platforms) became the engines of choice to power the second generation of S-10s. In compliance with the Clean Air Act, all second generation S-10s and Sonomas equipped with air conditioning used CFC-free R134a refrigerant beginning in the 1994 model year. The all new 1994 S-10 didn't offer any airbag, presumably as a temporary measure to economize the introduction of the new body styles, as well as to gradually phase out steering wheel designs that didn't accommodate for airbags, though the vehicle itself was slated for airbag capability.