Hey all, i am hunting a Random Misfire issue P0300, I have replaced the fuel filter, the spark plugs and have rotated a new engine coil through each of the positions. Still happening. I purchased a cheap smoker (Autoline - it works so much better than my home made one) and I have found one leak so far.

1. Can someone tell me the name of the hose so I can buy a new one

• I assume i need to take off the throttle body to replace this hose

Follow it back to your brake booster?

It goes into the fuse compartment and then it is kind of hard to follow without doing some disassembly.



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I think that one has a o-ring that you can replace if it's on the right hand side. If it is that one there is some trick to releasing it, but I don't remember the procedure.

I think you nailed it, i went out and just touched it and it fell apart. So now I just need to find the part number.

It looks like the vacuum hose that runs under the windscreen to the brake booster MJC5756DA

It looks like an attempt has been made to seal the connection, as the plastic retaining collar is missing.

Clean off all the foamy-looking stuff and you may find that the vac line is OK.

You should then be able to see the end of the brass ferrule in the TB. You will need a C2S15816 brake booster kit: this post shows what it looks like:
https://www.jaguarforums.com/forum/x...1/#post2389180

Strictly, you only need the o-ring and collar: you might be able to finagle the old o-ring out and the new one in without removing the TB.

^^^^^ This is the answer. From the pic, the pipe looks OK. That silly plastic grommet thing rots away and disintegrates over a couple of decades of heat cycles.