5 replies to this topic

[gavinwu]

hi i have  1997 rover mini japanese spec . half MPI and SPI.

 

i have used memsfcr and it appears to have a coolant fault or thermostat sensor fault once the coolant reaches around 85 degrees and 92 degrees on idle

 

the heater inside of the car blows hot air but im not sure if its fully working as there is only little heat

 

the hoses connected to the heater matrix one is hot and one is cold so im not sure if they are both meant to be hot.

 

the aux fan kicks in around 85 degrees

 

things i have a replaced a

 

82degrees thermostat 

water pump

coolant temperature sensor

 

im not sure what else i could check

 

any help would be appreciated

 

thanks in advance

 

im also unable to upload a log file

Edited by gavinwu, 12 June 2025 - 11:39 AM.

[MiniJosh92]

You need to have an 88 degree thermostat in there and sounds like your heater matrix or valve is blocked.

[gavinwu]

You need to have an 88 degree thermostat in there and sounds like your heater matrix or valve is blocked.

 

it came with a 82 degrees thermostat i just replaced it with the same .

 

would fitting a 88 degree make much difference as the temperature sill gets up to over 92 or is is because the memsfcr is programmed for an 88 degrees sensor?

 

the heater valve is moving and should be ok its just i am unsure why return hoses connected is cold. the hose connected to the valve is hot

 

does that mean i have to take out the heater matrix for a clean?

[Designer]

Hi.

 

It certainly sounds as if there is a blockage.

It could be the heater matrix is blocked or the return hose has collapsed internally or it could be the feed hose from the valve to the matrix has collapsed internally very near to the matrix or an air pocket block.

When I had this problem I removed the heater unit and flushed the matrix using the garden hose connected to the out let first then to the inlet. I did not bother to take the heater unit apart and remove the matrix.

I also removed both the feed and return hoses to make sure that they had not collapsed internally. They had not so the problem was with the matrix being blocked or an air pocket.

Since refitting the heater has worked as best as any Mini heater will work.

 

Paddy 

[roblightbody]

As far as I'm aware. all Rover Minis came with an 88C thermostat.

Edited by roblightbody, 13 June 2025 - 08:28 AM.

[gavinwu]

There was a blockage on the heater matrix valve, but now it has been cleared. I use the garden hose to flush it out. The heater now blows out hot air from both sides.

But the same problem still appears

What temperature should the coolant be at normally?