Coolant Issues that no thread has helped so far with!

[slym]

Hey all,

I have done quite a bit of research and here are just the facts:

I have a 2007 Mini Cooper S
few weeks ago I had a coolant leak in the housing, the car steamed up and I towed it home. So I bought a new thermostat housing and installed it no problem/no leaks

the problem:
after about 10 km of driving a code on my reader tells me that P0128 Thermostat below regulating temperature.
after a bit longer driving I get the code P0112B which I believe is a implausible temperature BMW/Mini specific

I thought it was the coolant sensor so I changed the new sensor with the old on, no change
I bled the system and still no change
I have looked on the cars computer while driving around and the cars temp is about 40C (at cold start) and after about 15kms of driving it is around 70C at the most.

My thoughts:
I believe it for sure it isn't the sensor
I don't think it is the thermostat stuck open/closed as the thermostat is brand new and I can see the temperature go down when I am driving (just small fluctuations)
I know the coolant level is good, and the mixture is right

If anybody can help me I will be eternally indebted to you!

[beken]

Well, late to the story but a few things can affect the coolant temp. Thermostat is one and you seem to have addressed that. The folks at BMW are very finicky about aftermarket parts so make sure the thermostat is a match to MINI's. Another might be you have a coolant clog somewhere so your coolant is not flowing out of the engine properly. When was the last time you flushed your coolant ?

Some things you should check, are any of your hoses sweating or worse, leaking? Anything older than, say 5 years, your hoses begin to dry out. The water pump on my BMW went after 8 years so it might be getting close.

Good luck.

[Pelican Parts]

I also second the Thermostat question. What t-stat did you purchase and install?