Most likely overfill and cheap expansion tank. But I am an avid believer that the 2 bar cap doesn’t help these cars survive the pressure at which your excess water should release if you overfill. You can get an e30 cap from BMW and it’s 1.4 bars.

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2006 4.8is, Black on White. SOLD Sniff Sniff.

2017 F85 x5m, Black on Red. BEAST MODE


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