K12 Automatic Overheating

[JustinKearney]

Hi folks,

I am looking for some opinions if I may. I am pulling my hair out at the moment with the wifes car. A 2004 Nissan March.

In a nutshell, its overheating. There is no temp gauge fitted, just a red light that comes on when its too hot. It happens at slow speed. Perfectly fine on motorways. Not leaking any coolant. If the light comes on around town, it will go off again with a bit of driving and airflow.

We have tried just about everything so far and I am stuck. This is what has been done so far.

• Sniff test completed. Tested negative.
• New radiator cap fitted.
• New thermostat fitted.
• Water pump removed and inspected. Perfect working order.
• Fan working correctly and switching between both speeds.
• Heater in car works perfect so the matrix is ruled out.
• Radiator was removed and tested. Was showing as partially blocked so a brand new one has been fitted.

So we just got the car back from the garage after having the radiator fitted. Expected that to cure the problem but although it has improved slightly the problem persists.

Really at my wits end with it now. Kinda hoping it will spontaneously combust. It looks like we will just put a new engine in, but at at cost of about €1,000. Does anybody have any suggestions before we do this?

Any suggestions would be greatly appreciated

 

[plmval]

Hi folks,

I am looking for some opinions if I may. I am pulling my hair out at the moment with the wifes car. A 2004 Nissan March.

In a nutshell, its overheating. There is no temp gauge fitted, just a red light that comes on when its too hot. It happens at slow speed. Perfectly fine on motorways. Not leaking any coolant. If the light comes on around town, it will go off again with a bit of driving and airflow.

We have tried just about everything so far and I am stuck. This is what has been done so far.

• Sniff test completed. Tested negative.
• New radiator cap fitted.
• New thermostat fitted.
• Water pump removed and inspected. Perfect working order.
• Fan working correctly and switching between both speeds.
• Heater in car works perfect so the matrix is ruled out.
• Radiator was removed and tested. Was showing as partially blocked so a brand new one has been fitted.

So we just got the car back from the garage after having the radiator fitted. Expected that to cure the problem but although it has improved slightly the problem persists.

Really at my wits end with it now. Kinda hoping it will spontaneously combust. It looks like we will just put a new engine in, but at at cost of about €1,000. Does anybody have any suggestions before we do this?

Any suggestions would be greatly appreciated

“Not losing any coolant” suggests that it may not actually be overheating when indicated by the warning light? This suggests a possible fault with the over temperature sensor and or indicator circuits?

Insufficient cooling water flow can be confirmed by removing radiator cap (when cold) and running engine up to temperature and checking radiator top flow with increasing rpm. (NB; do not drive with radiator cap removed)!

Inspect, test, diagnose and rectify insufficient flow possibly due to;

1. Air locks?

2. Defective new thermostat only partially opening?

3. Water pump impeller slipping on its driveshaft when in situ hot & under load?

4. Collapsed bottom hose and or water jacket blockages?

Happy hunting/diagnosing this fault!

 

[mcjs]

Check with a thermometer the coolant temperature, to verify that the thermostat opens regularly and the temperature sensor. You can use a multimeter with the thermometer feature.

 

[craig long]

Hello, im new to this forum and looking for help on a simlar overheating problem, when im driving on a motorway or dual carrage way at 70 the red light comes on, also when driving up steep hills the red light also comes on, normal driving the car is perfect, i have changed the thermostat and temperature sender but the problem persists, i have connected a OBD2 with live info and the temperature rises to 114 degrees when this happends, when its being driven round town not doing any heavy work its about 90 degrees, any help would be helpfull as im hoping to give this car to my daughter as she has recently passed her test but dont want her to be breaking down and leaving her stuck in the middle of nowhere.
thank you
Craig

 

[temakol]

Most of the cases if car not moving and overheated, the fan almost fail to blow the air to the engine bay...just replace it.

 

[Shawaaz]

flush your radiator with flush and re flush 3 times with water. fixed