Every once in a while I find a small puddle of white foam on the floor of my garage under the engine of my MCS. I once had a problem with a cooling sensor switch, but it was fixed by the dealer under warranty. Recently while waiting in a drive-thru lane the temp guage spiked again, but returned to normal as soon as I started moving again. When I got home I added about a pint of coolant to get it to the correct level in the recovery tank. It only happened that once, but I wonder if anyone has had this experience, and what to do now.

 

If the moisture on the floor is beneath the front-center part of the engine, have the thermostat housing checked - they crack and leak frequently. The MINI coolant system should stay full, unless it is leaking.

 

i'm getting a little better with NAM search - you might try these? they reinforce OldRick's post I reckon

https://www.northamericanmotoring.co...ht=overheating

https://www.northamericanmotoring.co...ht=overheating

 

I thought at one time the coolant recovery tank might have a leak, but the thermostat problem seems more realistic. Thanks.

 

Don't forget the PS fan, and the radiator fans. If either is defective, it will cause overheating when you're not moving. Turning on the AC should kick on the rad fan no matter what the engine temp. That got me home once when my sensor failed.
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