Help name this part!

[whitemage25]

Can anyone help name this part? It broke when I was replacing my plug wires. It looks like it is connected to the cooling system. What does it do and how much do you think it will cost to replace?

 

[hworksinc]

If you're talking about the little rectangle bolted to the engine, that's the DPFE (Differential Pressure Feedback EGR) sensor. It's part of the EGR (Exhaust Gas Recirculation) system.It's recommended to buy an OEM replacement, as the aftermarket ones are known to have problems.