You may still have an air pocket in the coolant system. Here are the instructions from Honda on refilling the coolant. They want you to leave the radiator cap off for 2 cooling fan cycles. This is so the thermostat will open and allow any trapped air to escape the system. Some shops will actually use a vacuum fill system to purge any air from cooling systems. But I'll find the service info on the sensor 1 for you as well so you have it.
Diagrams 2, 3, 4 are for ECT Sensor 1 replacement, you're having trouble with the connector in the picture 4? Those connectors that need to be squeezed together can be difficult sometimes. You dent want to break it, I will sometimes use a very small flathead screwdriver or a small pick with a hook on the end to pry very lightly under the connector tab while squeezing it by hand, to get the tab to release. You can also try pushing in at the same time. I know they can be a pain since it's been connected like that for so many years. In the 5th picture is what I use, just a very small screwdriver or pick just help get the tab to come up, be very careful though, don't force it.
When you do get it unplugged, make sure there is no corrosion inside the connector, that can cause it to be difficult to unplug as well. If you see green or white corrosion on the pins, either on the sensor or the connector, that needs to be cleaned out with some electrical terminal spray or the connector needs to be replaced.
On coolant sensors, some fail because coolant actually comes through the sensor into the connector and that also causes corrosion to occur.
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Saturday, January 6th, 2024 AT 11:58 AM