1991 BMW 525i Service and Repair Manual

This factory service and repair manual for the 1991 BMW 525i sets its scope at one car: a four-door sedan in Base trim with a 2.5L inline-six of 152 cubic inches — twin overhead camshafts, no forced induction, gasoline. The valvetrain is where this car asks for precision, and the manual answers with the clearances, timing procedures and torque figures the head demands, then carries the same discipline through the fuel, cooling, driveline, brake and suspension sections.

Engines covered

• 2.5L inline-six (152 cu in) — DOHC, naturally aspirated, gasoline

Body styles covered

• 4-door sedan

Trims covered

• Base

Known issues on the 1991 525i. Four recalls are recorded for this model year. One is the throttle housing bushing: broken, it lets the outer cable snag and hold the throttle valve open, so the car does not decelerate as expected. Another has a locking tab on the air bag contact ring breaking, the wiring parting after it, and the bag then unable to deploy. A third is a brake light switch that sticks on or off, and the fourth an overheating cooling system that can expel hot coolant from the heater core. Of 18 complaints, six name engine and engine cooling.