Water loss

[teammccrory]

Folks

My 2006 X3 D MSport is losing water.  My mechanic (BMW trained but not an actual BMW garage) says the head gasket on these never gives an bother.  Is he right?  I think I can see steam from the exhaust.  Any thoughts, please?

Thanks
Stephen 

[X5Sport]

Very rare, but like anything, possible.  How fast are you losing it?

Worth taking the oil cap off and seeing if there is any 'mayonnaise' on it.  That indicates water in the oil.

You will get steam from the exhaust until the engine/exhaust fully warm up.

Could be a leaking pressure cap on the overflow bottle which will allow steam to escape when at full temp.

Could also be a leaking overflow reservoir.

[jagr]

Check around the thermostats and front water hoses as any little crack under pressure can lose more than you would imagine.

[MarkG_M3CP]

Sounds like a faulty EGR Valve or cooler - very common on BMW diesels, the coolant leaks into the exhaust manifold. I would have it checked for cracks etc soon - my 335 almost left be stranded when it finally failed.

Have you experienced any misfiring or coughing, the car, not you as this is another symptom.