Consumer Guide's® Auto Editors have scoured repair bulletins and questioned mechanics to search for commonly occurring problems for a particular vehicle. In some cases we also give possible manufacturer-suggested solutions. In many instances these trouble spots are Technical Service Bulletins posted by the manufacturer, however, we have our own expert looking at additional vehicle problems.

Engine knock: The 3.2-L (S54) engine reportedly suffers connecting-rod-bearing failures at a higher than normal rate, perhaps because some car owners are not using the required 10W-60 synthetic oil which is not readily available in the aftermarket. BMW is extending the warranty to 6 years/100,000 miles, (2001-03)

Exhaust system: BMW issued a voluntary emissions recall to replace faulty crankshaft position sensors. (1999)

Steering noise: Steering wheel buzzes or vibrates due to poor isolation of the power steering pump. (1999)

Transmission leak: Manual transmissions' drain plugs may leak. BMW also suggests replacing the fill plug. (1999)

Transmission slippage: Transmission may slip and/or check-engine light may glow due to torque converter clutch (TCC) slipping and/or TCC solenoid failure. (1999)

This table lists costs of likely repairs for comparison with other vehicles. The dollar amount includes the cost of the part(s) and labor (based on $50 per hour) for the typical repair without extras or add-ons. Like the pricing information, replacement costs can vary widely depending on region. Expect charges at a new-car dealership to be slightly higher.

1999 323i/328i: Retaining clip that secures brake-booster pushrod to brake-pedal arm could detach from pin, allowing pushrod to disconnect, causing brake failure.

1999: Side airbag system is unduly sensitive to certain noncrash impacts, such as contacting large potholes or curbs at substantial speed; could deploy without an actual side crash. Battery Safety Terminal could also activate, disconnecting starter cable from battery, so engine could not be restarted after being shut off.

2000 323i/328i: Brake-lamp switch could fail internally, remaining either in "off" or "on" position; brake lamps would then either not operate or be continuously illuminated.

2001 315i/335i: On some vehicles, tires could lose air suddenly, affecting vehicle control.

2001 M3: Screws could fall into the parking-brake drum, reducing effectiveness or making screeching noises.

2001: Failure of engine-fan motor can cause electrical circuitry to overload and fail, causing fan to stop operating, with consequent engine overheating and possible engine damage.

2002 325Xi: There may be a crack in the rear brake rotor(s) that could expand due to braking torque, separating the brake drum from the disc.

2002 325i, 330i: The front strut could separate from the upper mount due to an improperly installed thrust bearing.

2003 325Ci/330i: Antiwindow pinching devices are not functioning properly on some vehicles. Dealer will inspect and replace all affected parts.