6 replies to this topic

[1963MKI]

I am a mini and rover 25 owner, I currently have an issue with my rover 25 so was hoping I could get some advice from rover K/mini conversion owners.

 

Right so, rover warms up well and no issues with power or rough idling or bad fuel economy BUT the temperature gauge in the cab never reaches full temperature.

 

Now, if left to idle with the heated windscreen on and the lights the engine will get hotter as the fan does come on but the gauge doesn't move at all above its position. So i suspect there is a problem with the temperature sensor but everyone i've spoken with says there is only one sensor that runs the ECU and the gauge reading comes from the ECU. So this doesn't make sense because I believe the ECU gets the correct reading either the gauge is faulty or there is a second sensor that runs the gauge.

 

There does appear to be two sensors coming from the coolant rail one with a brown lead and one with a blue. Can anyone clarify this issue ?

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[Jordie]

Pretty sure the ones ive had/worked on had 2 different sensors one for the gauge and the other for the ecu (fueling)

[slidehammer]

I have a Rover 214 a '92 model and I am sure that only had the one sensor feeding the ecu and the fan and gauge were controlled by the ecu. What you might find is the gauge is quite well damped and doesn't move very quickly, so doesn't register the temperature changes very quickly. I had a Rover 216 with the Honda engine in and that gauge went to normal and stayed there, so the first thing you knew when it was getting a bit hotter in traffic was the fan kicking in. But the gauge never strayed from normal.

[robminibcy]

I'm not familiar with the k series but on my vw golf the temperature sensor has 2 circuits, 1 for the gauge and 1 fir the ecu. If the rover has a similar setup to that that may explain the normal running but abnormal gauge reading

[dyshipfakta]

That gauge pictured is indicating normal running temperature isn't it? If fan is kicking in etc then atleast one of the temperature sensors is working correctly.
From experience in my k series Mgf the temp gauge never moved from the centre ie into the red. Even when it was boiling the nuts out of the coolant. If the gauge moves off of the bottom pin then it is probably working at least as good as it ever has done.

[dyshipfakta]

I also had a rover 211 that boiled itself completely dry of coolant and the gauge didn't move from the centre. It is essentially useless

[1963MKI]

I've solved it. Two sensors in the coolant rail. Remove one and the engine starts revving higher (engine thinks its cold probably) and the fan comes on (fail safe probably) but the gauge reads normal. Plug the first back in and it goes back to normal. Unplug the other one and the engine doesn't do anything but the gauge stops working.