Identify this for me

[DC2NoVA]

Anyone know what this is (the part with the green)? Doesn't look like it's in good shape and I'd like to replace it:


1988 m20 325is:



zoomed out:

[Cabriolet]

that is the thermostat housing and water temp sensors

[noneya54321]

temp sensors, brown plug is for the gauge and blue is for the ecu also missing a Valve cover nut look like :)

[QUKBMER]

LOL haha yep.

[DC2NoVA]

thanks! and I took that nut off earlier lol