Prior to replacing this part, I had the shop replace rotors and pads, valve cover gaskets and gromets, water pump and thermostat, drive belt and oil change. A day later, I noticed that there was a coolant leak and took the car back. When inspected, they found that the "part" was cracked. When I arrived at the shop they I saw the part. My mechanic had order it from the dealer and I volunteered to go get it to save time as the dealer is less than a mile away. The dealer invoice, which I have, says thermostat.

In the end, the shop replaced the part and I have no coolant leaks anymore.
You may be able to DIY - but you would have to drain the coolant first. Remove the hoses and replace the part. You would have to do this from under the car. It's easily accessible.


hope this helps