was replaced by Bosch K Jetronic. 1976 facelift With the introduction of the E23 7 Series, the E12 received a facelift in September 1976. The styling was overseen by Claus Luthe. The rear-mounted gasoline filler door was relocated to the side of the car and the taillights were widened. The hood was redesigned to a give a 'power bulge' which accentuated the BMW kidney grille, and the dashboard ventilation was repositioned to improve air distribution. As part of the facelift, the 520 model switched from the M10 inline-four engine to the BMW M20 straight-six engine, with the post-facelift 520 model often referred to as the 520/6. However, the M10 engine continued to be used in South Africa, due to local content laws. Even after the M20 entered local production in 1979, the 2.0-litre M10 continued to be available with "518" badges in South Africa. In other markets the only inline-four M10 post-facelift model available was the 1.8-litre 518 which carried on as the base model until the end of production. For the 525 and 528 models, the dual Zenith carburettors were replaced with a single Solex 4A1 DVG four-barrel, which increased power to in the 528. 1978 The 528i model, using Bosch L-Jetronic fuel injection, begins production in July as a replacement for the carburetted 528 which was discontinued in September 1977. 1979 535i Motorsport available as special order only 1980 M535i model introduced North American models Initially, the only model sold in the United States was the 530i, which was powered by a fuel-injected straight-six engine. Changes for American-market E12s include lower compression pistons, exhaust gas recirculation, an air pump and modified exhaust manifolds called Thermal Reactors. The North American E12 models had larger bumpers (designed to withstand a collision without body damage), which increased the overall length by . For the 1979 model year, the 528i replaced the 530i. To reduce emissions, the thermal reactor and air pump system were replaced with a 3-way catalytic converter and the car's Bosch L-jetronic fuel injection system was now fitted with an exhaust gas oxygen sensor. Power was reduced by , and the presence of the catalytic converter meant that unleaded gasoline (petrol) was required. Critical reception While being commended for its acceleration and build-quality, Modern Motor criticised the 1978 528i for unpredictable handling and excessive body roll. Steering corrections during cornering meant the car's body "lurches back annoyingly and messily",