BMW e39 5 Series Faulty Cooling System

Introduced to the United States in 1997, the BMW e39 five-series ended production in 2003 and had several variations in the American market, including the 525i, 528i, 530i, 540i and M5. The engines ranged from 150-190 horsepower and six to eight cylinders. A common problem among these Bimmers is a faulty cooling system, which if left unchecked could result in serious damage to these high-performance engines.

If the “Service Engine Soon” light illuminates on the dashboard, do not ignore it, your BMW is definitely trying to tell you something. In the case of the e39 5-series, it very well could be a thermostat failure. The thermostats are electronically controlled and are known to short-out. If this happens, they could melt portions of the wiring. This is especially common in the V8 engines. If at the same time you also notice the temperature gauge is climbing higher than normal, chances are you have a defective thermostat. Contact a local German import service expert to properly diagnose and resolve the issue before it causes further harm to the engine.

Another common cause for an e39 engine overheating is a faulty water pump. One way to test this is to see if your radiator is filled with coolant/water, and yet it still runs hot. This means the water is not being pumped to the appropriate areas to cool the engine. This problem could be caught prior to causing damage if you take your vehicle in for the regularly scheduled BMW Inspection 1 and Inspection 2 maintenance checks.

In rare cases, the e39 5-series has a defective radiator. Again, take the vehicle to an independent BMW service garage for proper diagnoses and inspection. They will be able to repair your car professionally and get you back on the road.

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