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BMW 330i Problems

Coolant Loss Due to Leak from Expansion Tank on BMW 330i

Problem Description and Possible Solution

An engine coolant leak may develop from the expansion tank resulting in engine overheating. When a cooling system component fails the entire cooling system should be inspected. It is not uncommon to find additional component have failed or are leaking.

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.

(16 people reported this problem)

BMW 330i Vehicles With This Problem

RepairPal Verified
Average mileage: 110,200 (45,500–160,000)
6 model years affected: 2001, 2002, 2003, 2004, more2005, 2006
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Viewing 1-4 of 4 comments
While driving home from my granddaughters dance recital, I heard the fans come on, then I received a message on the cluster board saying engine is beginning to overheat, drive moderately to cool engine, then within 2 minutes it said engine is overheated, shut car off immediately. I was like 10 blocks from home. Let the car cool off. Got car home, my son looked at the coolant reservoir and saw water leaking out, believing it has a crack somewhere on the bottom. I will now take it to a repair shop to see what they say it is. Any suggestions are welcomed. Thanks and have a fantastic day.
Crack in tank was a little difficult to spot. It developed very quickly and became a real gusher. Curiously, even though I believe both the replacement tank and the old cap were OEM, the old cap did not fit the new tank, so had to wait to obtain a new cap.