Can you identify this part and how to replace it? (pics)

[MakDad]

Hey guys.
Need some help.

Recently started having idling problems with my 4.6L XLT.
Used to surge RPM at idle between 600 and 1200. So thinking it was a bad IAC valve, I replaced with a new one. Now , no more surging, but the RPM at idle is around 300, almost sounds like it's stalled, but it's running.

So went ahead to isolate any air leaks I might have. The first place I squirted some starting fluid was around the throttle body ? I think it's the throttle body. It's the one where the two metal wire cables come to. The engine momentarily picked up RPM.

Then I made more "precise" squirts all around it. No reaction except when I squirted BEHIND the throttle body, at a round black part, with 2 hoses coming into it. The engine really picked up RPM.

So can someone please identify this part and let me know if and how to replace it ? Is it sucking in air and screwing up the air/fuel ratio ?

I'm attaching pics of it.

 

[docraymund]

It might be the vacuum control for the HVAC.

 

[raul94]

its for the pcv just did mine you can find it on ebay mine was doing the same thing.look for pcv valve hose .

 

[2004XLT]

+1 on the PCV hose. You can pull it off and inspect it, it's the larger one that leads to the blue PCV valve on the passenger valve cover. The rubber elbows rot out and collapse. You may be able to find an appropriate elbow from an autoparts store to save some money.

 

[MakDad]

+1 on the PCV hose. You can pull it off and inspect it, it's the larger one that leads to the blue PCV valve on the passenger valve cover. The rubber elbows rot out and collapse. You may be able to find an appropriate elbow from an autoparts store to save some money.

Yeah, took it off the following day, and the 90 degree bend in it was all "gummy" and had a hole thru it. Seemed like it overheated and made the rubber hose very soft and gummy.

I found a hose at home with a 90 degree bend in it, I believe it was 9/16" diameter. Popped it on (which was a pain to get to), and BAM, the engine idles fine again.