The gauge fluctuates when engine is not running/cold (my key is in the ignition). Also the engine light is illuminated. Does this point towards a faulty ECT sensor or something else?
Additional notes:
My heater core is leaking, and the thermostat/water pump/timingbelt probably need to be replaced.
Fluid levels are topped off.
What makes this problem better or worse?
nothing
How long has your 2004 Nissan Xterra had this problem?
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The circuit for the sensor needs to be checked. The gauge needs to be tested isolated from the circuit. The wiring should be checked for the power and the ground and for any shorts. And the sending unit should be isolated to see if it is contributing to the concern.
Naturally, those other areas need to be resolved also, but I do not feel like otherwise it's related.
