Check Engine Light and/or Engine Overheating on BMW 525i

The thermostat may fail resulting in engine overheating and/or illumination of the Check Engine Light. Replacement of the thermostat along with a complete inspection of the cooling system will be necessary to correct this concern.

Overheating can cause severe engine damage. If the engine begins to overheat it is recommended to stop at the first available location and have your vehicle towed to a repair shop.

RepairPal Verified
Average mileage: 105,265 (20,011–179,850)
7 model years affected: 2001, 2002, 2003, 2004, more2005, 2006, 2007
14 people reported this problem
4 people shared problem details
2002 BMW 525i150,000
My coolant thermostat became stuck open, resulting in the service engine soon light coming on, but now resulting in any overheating of the engine. My belief is that the coolant is always being put into the engine and the valve of the thermostat is just stuck so it will not close when the engine is off or cool enough to run efficiently. I need to replace the thermostat, but I don't believe the housing itself will need to be replaced as it is still in good condition and has no cracks or issues.
2001 BMW 525i20,011
Running hot then cool leakin green coolant getting close to runnin hot slow take off sound like air at first takeoff tank that water goes in get very hot bubbling at time
Engine light has come on several times do to several things [system misfire (spark plugs), air flow filter]
2007 BMW 525i35,000
water pump replacement. Light went on and overheating.
Related Items:
Two days ago...dash lights and one tail light(left) were fine...Dash message told me tail light...
when the car is idiling,it will start to shake pretty hard until i start to drive then it will...
Can you just replace a shroud without replacing the radiator and the clutch?
what to do when engine light apears
Have had front/rear brakes redone - driving along - check engine light comes on plus the brakes...

Related Content