tstat

no floor puddles....just the need to constantly top off the coolant...car has less than 40K miles....any informed or experienced ideas?

tstat

forgot to mention it's a 2.7T

MP4.2+6.0

It can often leak on something hot and just evaporate. Look for the pinkish powdery residue, first underhood, then underneath. That's the most likely. If you smell it in the A/C system, that of course isn't good (heater core), but at least would tell you where it is. Least likely is an internal motor problem and it's going out the exhaust. Big clouds of steam on a cold day is the tell tale sign here.

Fortunately usually it's just a small leak. See if the 2.7T guys know more specifically typical trouble spots.

audikillsbmw

pump is leaking. That's a fairly common problem with the turbo C5's.

S4_Cinci (I S'edTFA)

i.e., lack of dried pink crusty stuff, then #2 source of leak is the oil "cooler" and if you don't see any sign of leak or smell coolant while engine is hot, then look inside your crankcase - there have been problems with this on the B5 S4. Usually happens after more miles, but you never know. Oil analysis is the best way to find this out, but if you find external leak signs, then you should be fine after you fix that.

Boston Driver

Agree...I had that issue on my 2.7T, covered by CPO

tstat

thansk everyone...off to the dealer...still under warranty!!!!

audikillsbmw

Good luck! : )