In this issue:

Fuel Pump Diagnosis

A no-start on a good customer’s E46 looked like it was due to a fuel-supply problem, but automatically installing a pump would have been a dereliction of diagnostic duty.

E90 Steering Angle Sensor

A pattern failure may indeed point you to a bad component, but when the part is expensive you want to be very sure it’s the culprit before you replace it.

VANOS Variable Valve Timing

Valve diameter, lift, and overlap are all contributing factors to the volumetric efficiency of an engine. If you can vary the relationship between the intake and exhaust valves you can broaden the power band and still have a smooth, clean idle. Variable valve timing is a great advance — as long as we can keep it working.

Frozen Matt Paint

BMW Frozen and Individual Matt paints create a soft sheen instead of a mirror-like shine. The satin finish is elegant and stylish, and is selling out faster than the company can produce cars with this dramatic look.