Nissan micra 2006 1.2 - Nissan micra overheating

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Thu 19 Jul 2018 11:36
Nissan micra 2006 1.2 - Nissan micra overheating - KCSRenault
Hello my grandmothers car has recently been overheating, although the symptoms are slightly strange. If the car is driven with the heater on hot and fan at full speed the car will not over heat, even if driving at 70 mph for around an hour. However if the car is driven at 70mph with the heater on cold. He car will overheat after around 30mins.

The car has just had a new water pump, thermostat and he radiator flushed in order to try and solve the problem.

The fan kicks in as it should, there’s no water and oil mixing.

The garage is confused. They have sniff tested and pressure tested but no signs of anything.

Any ideas or previous experiences, even the Nissan dealership are lost with it, and when it overheats it’s not like an inferno of coolant or anything, just hotter than it should be.

One as patrol said that the fan was only kicking in when the car was too hot, but it will kick in before the warning light comes on,

Any advice much appreciated
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Thu 19 Jul 2018 11:52
Nissan micra 2006 1.2 - Nissan micra overheating - elekie&a/c doctor
How do know it’s overheating,as there is no temp gauge?
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Thu 19 Jul 2018 12:45
Nissan micra 2006 1.2 - Nissan micra overheating - Cris_on_the_gas

Might be an air lock in the cooling system after it has been drained due the the work mentioned.

Have you tried running the engine to normal temperature but with Radiator cap removed, have know this to exclude air pockets.

Edited by Cris_on_the_gas on 19/07/2018 at 12:45

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Thu 19 Jul 2018 15:02
Nissan micra 2006 1.2 - Nissan micra overheating - KJP 123

If I notice my temp gauge rising I switch heater and fan to max; it acts as a second radiator.

Maybe despite flushing rad is still blocked. You might be able to check for cold spots with an infrared thermometer which are quite cheap.

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Sat 21 Jul 2018 12:07
Nissan micra 2006 1.2 - Nissan micra overheating - Peter.N.

In the past this problem has always been for me that the radiator is flow is obstructed, doesn't usually happen now as the modern permanent antifreeze tends to stop corrosion, but the fact that the heater is pulling the temperature down indicates that the radiator isn't.

I would suggest that you disconnect the bottom hose and put a hose from the tap into the filler and see if the water is running out as fast as you are putting it in, if it overflows the radiator as partially blocked.

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