This is an FYI for anyone taking on the Valley and Octopus hose replacement.

After buttoning everything up with the intake manifold all torqued down and full of coolant again I started the car. At first it was all normal but after a couple of minutes the revs would not settle down and she idled rough. When I went to the engine compartment I could here a sucking sound that was obviously a vacuum leak. After spraying some carb cleaner around I determined it was at the bottom of the throttle body. I removed the manifold again, now have this job down to 15 minutes.
There is a hard plastic vacuum line that inserts into the lower passenger side of the throttle body with a plastic quick disconnect. One of the for retaining features on the clip was broken allowing air in. This clip is not obvious as it remains on the vacuum hose inside and asbestos and foil heat cover which you would have no reason to look at, and does not come out with the throttle body.
I took the vacuum line to the Jag dealer as I figured I probably had to order the whole line to get the clip. The dealer cannot figure out a part number for me and has sent pictures of to the UK to try and figure out a part number.
Meanwhile with an "O" ring and some sealing tape I have managed to put it back together. If I do get the part I can install it without removing the throttle body. Everything is running well now.
I realize that the line in question is probably part of the vapor recovery system but vacuum line seems more understandable.



Throttle Body upside down to show the location and broken clip.



This is the line I will probably have to order to get the clip.

 

I had the very same problem with my 99. Use this link and scroll down near the end and you will see the connector.

Link JagRepair.com - Jaguar Repair Information Resource

 

See if this helps.

 

Photos of fitting

 

Thank you for that information, even though that little fitting is $23 Canadian that is still better than $74 for a hose I don't need.

 

I got the fitting Gus suggested and it fit great. They do not list the P/N for the XK8 but they do for the brake vacuum Booster on an S-type. My Jag dealer parts guy is also an XK8 owner so he says he will salt that useful piece of information away for future use. I don't know how I would get along without the help of the people on this forum. Thanks again.

 

First - I'd just like to say that this forum is the ONLY way I can maintain (or afford to maintain) my Jags. Thank you experts and newbies alike - your problems are my problem, and the solutions are ... well, just fantastic.

That said ... when removing this line from the throttle body - how do you detach the line *without* breaking that marvelous little hidden un-intuitive connector?

Thanks in advance!

 

Just press and hold the black plastic locking collar into the brass? bush & then pull the line out.

The mechanics of it are similar to the 'push fit' plumbing fixings

 

Marvelous! Many thanks!!

 

Worked a treat!