[Will maddox]

Seem to be losing coolant, getting a fairly big patch on my driveway after a spirited drive.
Before I have a chance to go have a look on my day off, is there any common detects to look for?

Will

[abeardo83]

I believe the expansion tank is normally the culprit. Thankfully they're not that expensive, or difficult to replace.

Have a look on http://www.pelicanparts.com/BMW/tech..._main_e90.htm.

There's a section on replacing the tank, but also how to test for leaks.

[dm2583]

When i had coolant leaking, turned out to be the water pump

[Will maddox]

Had a quick look last night with the torch and seen down the very front n/s down by the radiator/intercooler/condenser on the undertray some. Coolant stains

Any ideas

[Chappers 71]

When I fitted my uprated inter cooler I found my rad had been leaking at the bottom rhs corner. I hadn't noticed it using much coolant, must have just caught it in time.