Need help with identifying what's this hose about and how it is called?

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CitroenXP
Posts: 10
Joined: 07 May 2026, 23:07

Need help with identifying what's this hose about and how it is called?

Unread post by CitroenXP »

Hello good forum,

I need a bit of help. I just realized that the leak I was looking for is coming from this hose:

Image

I don't have any clue what it is called and where is it going? It seems like continuation of the PCV hose/valve. Anyone can help?
kingjafad
(Donor 2026)
Posts: 80
Joined: 22 Dec 2022, 13:03
x 8

Re: Need help with identifying what's this hose about and how it is called?

Unread post by kingjafad »

Hi, Im not sure i recognise the engine, but generally that red dotted pipe will come from the crankcase breather on the right, the intake in the middle and perhaps the oil separator somewhere on the left/rear . https://www.underhoodservice.com/pcv-system-dtc/ Thats just my gut feeling.

Edit seems its a KFT engine?
Just found this https://www.ebay.co.uk/itm/336351053614
The picture looks like it should go to some valve/solenoid (brown in the picture) - Not clear where yours is going.
Last edited by kingjafad on 08 May 2026, 22:38, edited 1 time in total.
CitroenXP
Posts: 10
Joined: 07 May 2026, 23:07

Re: Need help with identifying what's this hose about and how it is called?

Unread post by CitroenXP »

kingjafad wrote: 08 May 2026, 22:18 Hi, Im not sure i recognise the engine, but generally that red dotted pipe will come from the crankcase breather on the right, the intake in the middle and perhaps the oil separator somewhere on the left/rear . https://www.underhoodservice.com/pcv-system-dtc/ Thats just my gut feeling.
Hmm, I don't know. First I should say I don't understand a whole lot of engines (obviously I guess) but that cracked hose over there is making the engine to shut down when I slow down the car and the revs go down fast I guess. I goes worse when the weather is wet and humid. And I clearly hear it whistle when release the gas manually from the throttle body. I mean if it was running oil inside shouldn't it leak oil? Or maybe it's just small oil vapor that can't leak so easy. I don't know. I'll try to follow it tomorrow morning to where it goes.

P.S. I wonder if I cut 1-2 cm. from the end of the hose and put it back I should work fine in theory. Maybe I'll try that tomorrow too.
Last edited by CitroenXP on 08 May 2026, 22:50, edited 1 time in total.
kingjafad
(Donor 2026)
Posts: 80
Joined: 22 Dec 2022, 13:03
x 8

Re: Need help with identifying what's this hose about and how it is called?

Unread post by kingjafad »

Its a breather pipe, so will have fumes/air in it, but its not full of oil if thats what you are thinking. It may be oily but thats from the fumes/residue in the crank breather. The fact that its leaking is your problem. You could find the exact point of the leak and just tape it up as a temporary fix until you get a new pipe (its not under massive pressure).
If yours is actually leaking oil then there is something wrong with the PCV in the cam cover (right in your picture) on the top as that is realistically where that oil would be coming from.
CitroenXP
Posts: 10
Joined: 07 May 2026, 23:07

Re: Need help with identifying what's this hose about and how it is called?

Unread post by CitroenXP »

kingjafad wrote: 08 May 2026, 22:48 Its a breather pipe, so will have fumes/air in it, but its not full of oil if thats what you are thinking. It may be oily but thats from the fumes/residue in the crank breather. The fact that its leaking is your problem. You could find the exact point of the leak and just tape it up as a temporary fix until you get a new pipe (its not under massive pressure).
If yours is actually leaking oil then there is something wrong with the PCV in the cam cover (right in your picture) on the top as that is realistically where that oil would be coming from.
No it's actually not that oily. I made the picture right after I sprayed some detailing spray to look for the leak.

As I said above maybe I'll try and cut few centimeters from the hose's end and put it back.
wheeler
Posts: 7916
Joined: 21 Sep 2002, 19:07
x 1056

Re: Need help with identifying what's this hose about and how it is called?

Unread post by wheeler »

The pipe goes to the charcoal canister electrovalve. on the ebay picture this is the brown valve which i separate from the canister. Or sometimes further along the line, follow the pipe & it will disapear into the wing/
On some later models the electrovalve & canister are usually an all in one unit & is located under the OSF wing, the pipe should only contain fuel vapor.
CitroenXP
Posts: 10
Joined: 07 May 2026, 23:07

Re: Need help with identifying what's this hose about and how it is called?

Unread post by CitroenXP »

wheeler wrote: 09 May 2026, 08:34 The pipe goes to the charcoal canister electrovalve. on the ebay picture this is the brown valve which i separate from the canister. Or sometimes further along the line, follow the pipe & it will disapear into the wing/
On some later models the electrovalve & canister are usually an all in one unit & is located under the OSF wing, the pipe should only contain fuel vapor.
Interesting why I'm not getting any EVAP DTCs but just engine low rev problems.
wheeler
Posts: 7916
Joined: 21 Sep 2002, 19:07
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Re: Need help with identifying what's this hose about and how it is called?

Unread post by wheeler »

Only the electrical circuit is monitored, as long as the circuit is good and the electrovalve is working then i dont think it will detect a fault.
CitroenXP
Posts: 10
Joined: 07 May 2026, 23:07

Re: Need help with identifying what's this hose about and how it is called?

Unread post by CitroenXP »

Okay I saw it it really goes into that brown EVAP solenoid. I went to cut the hose and put it back into the nozzle a bit shorter but the hose had become very hard and brittle so I just rolled a bit of electric tape around it. Now I don't know can I buy just this hose to replace it or does it come together with a new EVAP solenoid? How is this hose called even? EVAP vacuum hose?
ozvtr
Posts: 873
Joined: 13 Oct 2020, 01:11
x 243

Re: Need help with identifying what's this hose about and how it is called?

Unread post by ozvtr »

This is my best guess from the photos.
EVAP.jpg
Your part is item 7 (not 6 which is highlighted). The Citroen part number is 1505 XP.
I'm either right or I'm wrong. Is there a push on connector at the fitting of the inlet plenum? Does the diagram roughly fit your car?
My references do not show that the Xsara Picasso has a TU3 engine!? The closest to your photo is the Xsara II.
You could possibly just replace the tubing with an appropriate sized nitrile rubber hose. It's not under pressure so it wont pop off. It's only venting excess fuel vapor from the top of the fuel tank.
Without the engine running, the purge canister valve (item 2) is closed. Excess fuel vapor, from the top of the fuel tank, is collected by the the purge canister or charcoal canister (item 1). When the engine is running the engine ECU will open the purge valve (only at certain times, not all the time). The vapor from the purge canister goes into the inlet and is burn by the engine.