Need help identifying a part

[Blueberryyum02]

Ok let me give some history I have 02 ls v8 for some time I kept hearing a faint hiss, that sound like it was coming from the throttle body area, recently I have been having a issue that's causing the engine to bog down while at a stop light, tonight I went out on a drive when I got back to my driveway, I popped the hood and start listening for this hiss to narrow it down, the two vacuum lines that plug into the top of throttle the rubber boots have been replaced, i found out my throttle position sensor was loose so I, removed the IAC tighten it down while adjusting it,so the RPM sit in between The notch before one, I'll call it the the first and second line before you hit one. I cleaned the IAC placed it back on.

Noticed a increase in performance, tonight I was rechecking the vacuum lines and I notice a black box on the firewall that had a gray electrical plug stuck into it with two vacuum lines, as I reached back. To move the line, to see if it would hiss one of the lines just fell completely off with little to no effort. What is this parts purpose and niame so I can replace it.

I think this was my problem all along the faint hiss that I have been hearing.

The image might be a bit dark was useing cell phone to capture image of the part.

Thanks for you guys help and advice in advance.

 

[lincolnelite]

could be the egr sensor (too dark), no check engine light?

 

[86markviilsc]

It's part of the EGR system. I can't recall the name at the moment. If you haven't thrown an EGR code and possibly lean condition, it's not far off. That part is somewhere around $20.

EDIT: EGR Pressure Feedback (DPFE) Sensor
Also wrong on price, Rockauto lists it for between $35 and $60

Edit 2: Motorcraft part number F77E-9J460-AB

 

[Blueberryyum02]

It's part of the EGR system. I can't recall the name at the moment. If you haven't thrown an EGR code and possibly lean condition, it's not far off. That part is somewhere around $20.

EDIT: EGR Pressure Feedback (DPFE) Sensor
Also wrong on price, Rockauto lists it for between $35 and $60

Edit 2: Motorcraft part number F77E-9J460-AB

Thanks for the info, I haven't thrown a code yet cause it happen when I got home and parked, while checking all vacuum line connections, so I just shut it off and will go grab the part in the morning. I think it was already dry rotted and me moving it was the catylst for the last piece of good plastic holding it together to give.