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Oil Temperature is showing -40 degrees

Crowther1009
Crowther1009
in Ford Fiesta Club

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Having problems with my mk7 Fiesta 1.4tdci. After head gasket replacement, there’s still a lot of smoke.The oil temperature is showing as -40C and I’ve changed the pressure switch. Any ideas??

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    did a garage do your head gasket. What colour smoke comes out the exhaust, white smoke tends to be burning oil (possible piston ring) black smoke dirty diesel injectors need looking at or clogged particulate filter. Pressure gauge could this be wired round wrong way.

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    • Author

    A garage yeah. It’s white smoke, we’ve had the engine changed, new injectors, cylinders done. We’ve tried a partial regen and it seems to smoke less. Wrong wiring could show incorrect temperature reading? It’s only got one wire to the switch.

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    How are you measuring the oil temp? Didn’t think fiestas had a oil temp sensor.

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    I suspect that indeed there will not be an oil temperature sensor.

    -40 degrees Celsius is the default value when no temperature sensor is connected or the temperature sensor is defective (infinite resistance). If the oil temperature is monitored by the PCM it will generate a DTC code if the sensor is not connected or defective. 

     

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    • Author

    So running in a diagnostics machine, it’s coming up with this? 

    119021F5-CB27-484A-9A3C-7B8FAF282140.jpeg

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