I'm trying to replace the coolant temp sensor (temp gauge sensor - black connector) in my van.
By that I mean reinstall the original sensor which popped out when I inadvertently removed the clip.

I pushed the unit back in the hole and reinstalled the clip but then I noticed it had a lot of wiggle and I was easily able to pull it out. What is going on here? Looking at the unit I see no groove for the clip to catch on to.
Either I am missing some part that fell off or I am doing something wrong. The only thing I can think of is the o-ring must not be pushed all the way back and the clip holds between the unit and the o-ring. But I don't see how this would prevent the unit coming off? The other possibility is the coolant temp sensor and temp II sensor clips are not interchangeable and I got them mixed up (they looked the same to me).

I hope someone can answer soon as I wanted to get this done this morning and refill the coolant before it hits 100 degrees here in AZ.

David (1987 Wolfsbug, currently coolant-less)

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