We've identified 4 known issues that can affect the 2003 BMW 5 Series (E60/E61). 3 of these are serious faults that could be expensive to repair.
The plastic or metal swirl flaps in the intake manifold can break and be sucked into the engine, causing catastrophic piston and valve damage.
The active steering rack uses a planetary gear and electric motor to vary the steering ratio. Sensor failures or wiring issues can lead to an off-center steering wheel.
The MPM and other modules are located at the lowest point of the boot. Blocked sunroof drains or boot seal leaks can flood the area and fry the electronics.
The early "CCC" iDrive units are prone to internal hardware failure, often caused by capacitor or solder issues due to heat.