Tag: ECT

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DIY: 1998 V70 ECT (Engine Coolant Temp) Sensor Replacement

So, when it is cold, the ECU injects extra fuel to start the engine. The problem is, when the ECT fails, it usually fails in “HOT” position (short-circuit inside the sensor), I have these 2 symptoms:

Aux fan runs on its own for about 6 minutes or so.
Hard start when COLD (ECU thinks it is hot and no need to inject extra fuel when it is COLD).