Hose in Throttle Body

Ok friends, this is a 2000 model 3.0 V6 with 230,000 miles.

I’m chasing down an air leak, and my JTIS CD-ROM manual has gone haywire and I can’t open the fuel and air sections (error: ViewPort Application: can’t resolve link), so its time to play our favorite game,
"What’s this hose?"

Here are the clues for our contestants.
Rubber elbow at the back of the engine, rubber connector hose going down behind the engine, black plastic tube going forward.

The other end of that black plastic tube feeds into the throttle body downstream of the throttle plate.

Can anyone identify that hose?
The winner gets a day of all-expense-spared bragging rights.

I think the air leak might be down behind on that connector hose.
Do I have to take off the wiper box cover to get to it?

Well, I took off the wiper cover and cross beam so I could see in there better, and I found the trouble, a crack in the big connector hose down below the rubber elbow.
I tried to get it off in one piece but it broke apart.

Its a transition hose from 3/8" to 5/8" ID and there is a metal pipe under it that seems to go forward under the intake manifold, but I can’t see where it goes to.

Looking around I also found another 3/8" ID x 3" long hose connection on the bottom of the throttle body opposite to the one on top. This one connects to another plastic tube which goes to the brake booster. The hose looked about ready to fail so I will replace it as well.
So I suspect this one on top is also a vacuum source for something, but what needs a 5/8" pipe? Transmission?

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I found out what that hose is. There was a posting on jaguarforums.com about it in 2012 from somebody having the same symptoms as me, stalling and rough running caused by a vacuum leak, and it is an oil separator breather hose part number C2S50039.
I ordered one on ebay from Impart1731 in Austell Georgia. The description doesn’t make any sense, 57mm x 35mm, but the picture looks right, so we’ll see when it arrives.

My new JTIS CD and the C2S50039 adapter hose arrived today and it is correct. The description 57mm x 35mm must have been written by somebody who saw the size written as 3/8" x 5/8" or .375" x .625" or something and never heard of inches so they figured it must be millimeters and made a wild guess.

I can’t find any mention of this hose or any description of the PCV hoses in the new JTIS CD manual. It just says there are “several hoses”, no picture.

BTW installing the new JTIS took 2 hours because there is something they don’t tell you in the README.pdf instructions.
You have to search in C:\Windows\System32 for cmd.exe and select and right click it and select Run as Administrator.
Then you are in the operating system, a place I haven’t been in many years.
When README says to copy this command:

C:\Windows\SysWOW64\regsvr32.exe "C:\Program Files (x86)\Common Files\microsoft shared\DAO\dao350.dll"C:\Windows\SysWOW64\regsvr32.exe “C:\Program Files (x86)\Common Files\microsoft shared\DAO\dao350.dll”

and paste it to:
you can’t just highlight the whole command and copy it because there is a line break and you won’t get the whole thing. Copy and paste each line and be sure you have just one space between the first and second pastes.

All that just to replace a little hose. :exploding_head:

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I think that the files you have to copy as Administrator might be because JTIS was written for 32 bit Windows and this workaround makes it run on 64 bit machines. Could be wrong about that, it’s just a guess.


Thanks, I suppose you are right. This is a Hewlett-Packard with Windows 8. I would understand it better if it was a Packard 8 with Hewland gears and plate glass windows. :nerd_face:


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