The Bosch L-Jetronic system is used on all U.S. Spec Alfa Romeo GTV6s, Milanos, and 1982-1989 Spiders, BMW E12 5 series and various 3 series cars, The Datsun 280Z and 280ZX, All U.S. spec fuel injected Fiats and Lancias, The 1984-1989 Nissan 300ZX, The Toyota Supra Mark 1 and many others.
This article is my old GTV6 L-Jetronic article altered by Eric Russel for the Alfa Romeo Spider. It's also substantially improved with some great pictures and diagrams. The basic information is essentially the same as the older GTV6 article but if you have a Spider it will be easier to follow along here. NOTE there are some significant variations between the GTV6 and Spider systems so try to use the correct article.
This article is intended to help owners of cars with Bosch Motronic Fuel injection perform their own service. The article is based on the Original Bosch Motronic system used on the 1987 E28 BMW 535i.