ECT SENSOR EXCESSIVE TIME TO REACH CLOSED LOOP
While engine is warming, PCM reads Engine Coolant Temperature
(ECT) sensor to determine how long it takes coolant to reach
temperature required for closed loop operation. PCM compares actual
time required to a predetermined time.
You will likely not notice any drivability problems. Only the SES light.
- Insufficient warm up time
- Low engine coolant level
- Leaking or stuck open thermostat
- Faulty coolant temperature sensor
- Defective ECT sensor
The easiest thing to do is to reset the code and see if it comes back.