1999 BMW 323

Engine Cooling problem
1999 BMW 323 6 cyl Two Wheel Drive Automatic 80,000 miles

recently aux. Tank was replaced. Now error message/ low coolant and leak. Thermostat went to hot and immediatley came back to center reading. Leak does not seem to be coming from aux. Tank, but where? Is it thermostat, 0-ring, sensor wire? What?
Anouk 1959
November 3, 2009.

I cannot see it from cyberspace, and if I were there, I would start with pressure testing the cooling system. It could be the tank, or the radiator or a hose.

Dr. Hagerty
Nov 3, 2009.