Our 2009 Clubman S (62,000 miles) has started to overheat. Two weeks ago the yellow overheating light came on, and when I checked, the expansion tank was empty of coolant and the oil was down a quart. I couldn't see any sign of coolant leak, so I topped the coolant and oil up and had my wife keep driving the car. Today the yellow overheat light returned, and when I checked we were down on coolant and oil again. I took the intake off so that I could see the thermostat, and pulled the passenger-side wheel well liner to look at the water pump, but still can't see any signs of leaking. The oil consumption seems a bit high even for a turbo engine, and I cannot figure out what is happening to the coolant. I change the oil every 5000 miles and the coolant every other year. Any ideas where the missing coolant is going? There is no white smoke on acceleration and no frothing in the oil, so I'm not focusing on a blown head gasket yet.

 

Think I found it. Liquid on the bottom of the transmission, and a leak at the seal for the temp sensor on the thermostat. Off to order parts!

 

Ironically, I have the exact same thing going on right now. I'm taking the Coupe in tomorrow to the dealer.

Weird...

Did you notice any drops of oil on the ground?

 

No oil on the ground, I think the oil use was from a hotter-than-normal turbo engine. I did finally find the coolant leak when I jacked the car up and refilled the expansion tank. A few drops made it down to the bottom of the transmission case, and could just barely be tracked back up the side of the engine.