1990 BMW M3 Service and Repair Manual

This factory service and repair manual for the 1990 BMW M3 covers a car whose mechanical specification reads short: a 2.3L inline-four, double overhead cams, no turbocharger or supercharger, gasoline, in one two-door coupe body sold in a single trim. The benefit of that is that every clearance, every torque figure and every wiring path applies to the whole car rather than to one variant among several, and the sections are ordered by system so a job can be looked up where it actually happens on the vehicle.

Engines covered

• 2.3L inline-four — DOHC, naturally aspirated, gasoline

Body styles covered

• 2-door coupe

Trims covered

• Base

Known issues on the 1990 M3. Coverage runs from engine mechanical outward. The 2.3L four gets its specifications, torque sequences and diagnostic procedures; the fuel, ignition, cooling and exhaust systems that hang off it get theirs; and the manual then documents the transmission and driveline, the brakes, the suspension and steering, the heating and ventilation, and the wiring behind the coupe's dash and doors. Diagrams are drawn for the equipment this single-trim car actually carries, which is what makes an aging chassis harness traceable end to end.