2008 Mini Clubman S persistent 2F07
 

Had this vehicle come in for a failed thermostat, which was cracked along the same seem they always seem to fail at. Vehicle had no current engine codes, and appeared to have not suffered any major damage from overheating. The thermostat was replaced with a Rein unit (rate at 108 Celsius) through Pelican along with the plastic coolant pipe that inserts into the back of the water pump.

After installation, the car drove fine and seemed to behave normally as far as cooling fan operation but after it was returned to the owner the check engine light came on for this code (2F07). Observing the car with a scan tool while driving, it took quite a while to get up to temperature and only saw a max temperature of around 207 Fahrenheit. Eventually the same code returned.

Nothing else seemed to be wrong with the car, so the thermostat housing was replaced with the same type of Rein unit. Driving the car this time during an extended trip, it was only able to achieve a maximum temperature of 215 Fahrenheit, with average cruising temps around 205 F. Eventually the same code returned again. I find it unlikely that I received two bad thermostats in a row.

The system is bled properly to the best that I can tell, and I haven't had this issue with any of the other Minis of this generation that I've replaced the thermostat on before. Any thoughts out there on what I should look at? Thanks

No thoughts?

Bueller? Anybody? Anybody?

Okay, BMW was tight lipped about resistance values across that MAP thermostat device and about any expected wave form for a lab scope when the thing is operating properly, making it difficult to test either of the Rein units I had beyond wiring continuity and verifying voltage supply. So I spoke with the owner and decided to try the OEM BMW part.

The car displayed a steady ability to operate in the correct temperature range with no issues and no return of code 2F07.

Before I knew it could potentially be the problem, I installed the same Rein thermostat housing in a 2012 Clubman. That model is running the N16 instead of the N14 engine, and is an automatic. Not sure how different the desired temperature is for normal operation between the two models, but if the code comes back on that car too then it seems like a decent indicator that their could be a batch of weak Rein units running around. I'll follow up if I have anything further.