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Mini Mpi Overheating

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#1 915Davidg

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Posted 14 January 2019 - 11:37 AM

Hi All,


So I bought my first mini in the summer  :proud: but have had non stop problems with overheating since. If I drive it for 5 mins in stop/start traffic it boils over and loses coolant. So I have replaced the following so far but still no fix:


- Thermostat

- Thermostat harness/ wiring

- Temp Sensor

- Expansion tank/ 2 x caps

- Water Pump

- Radiator


I have also taken it to a garage to check the head gasket and that all seems fine. They seems to think it could be a faulty ECU because the fan is coming on too late. One more thing to note is the temp gauge in the car isnt readin properly (barely moves even when overheating).


Any ideas welcomed and I can't think of anything else :(


Thanks in advance,



#2 pete l

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Posted 14 January 2019 - 02:07 PM

The fan is coming on then ? if it is, then you probaly have a coolant system that is not getting up to pressure, so it will boil at 100°c.


A system under correct pressure will not boil until over 106°c or more. The cooling fan comes on at 104°c.

Edited by pete l, 14 January 2019 - 02:07 PM.

#3 ukcooper


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Posted 14 January 2019 - 09:38 PM

heater matrix blocked

Edited by ukcooper, 14 January 2019 - 09:40 PM.

#4 Fast Ivan

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Posted 17 January 2019 - 09:13 AM

If I drive it for 5 mins in stop/start traffic it boils over and loses coolant. 




Find where it's losing the coolant from - this is most likely your problem

#5 Midas Mk1

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Posted 17 January 2019 - 09:16 AM

Are you bleeding it properly for air? Might have one massive airlock, MPi's can be harder to bleed than earlier minis with side mounted rads.

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