C5 X7 120 kW 2.0 HDi fuel rail broken

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Vojta15
Posts: 4
Joined: 24 Dec 2023, 09:40

C5 X7 120 kW 2.0 HDi fuel rail broken

Post by Vojta15 »

Hi everybody.
Engine runs perfectly fine, accelerates pretty well when I hit the gas. The problem is that there is a pool of diesel around the injector (I replaced leak off pipes, no effect). After cleaning the top of the enigne I found diesel around the first injector and also behind the fuel rail, there is a small room behind injector 1 and 2. After driving a little more, the diesel gets around injetor two and remains in the room behind the fuel rail. So I suspect the fuel rail is broken somewhere there.

Is it possible to have the fuel rail (just a tiny little bit) broken and not see any bad performance of the engine? I would expect some faults regarding the fuel pressure that leads to turning the check engine light on at least... Maybe the fuel rail was torqued down too much and that caused that it broke? Thanks for helping, cheers :)
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CitroJim
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Re: C5 X7 120 kW 2.0 HDi fuel rail broken

Post by CitroJim »

Vojta15 wrote: 06 Jan 2024, 20:09 Is it possible to have the fuel rail (just a tiny little bit) broken and not see any bad performance of the engine?
Yes, it is. I once had a tiny fracture in the pipe between the High Pressure pump and rail on a Xantia HDi engine. The fracture (near one of the unions) was almost microscopic but enough to weep under the very high pressure in the rail.

There was no effect on performance or any fault codes.

A good clean-up and then a short run should show where your leak is originating.
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...
Vojta15
Posts: 4
Joined: 24 Dec 2023, 09:40

Re: C5 X7 120 kW 2.0 HDi fuel rail broken

Post by Vojta15 »

Thanks Jim. I did few cleanups and test drives and ti looks like it is leaking from the rail. I post here later if replacing the rail solved the issue.
Vojta15
Posts: 4
Joined: 24 Dec 2023, 09:40

Re: C5 X7 120 kW 2.0 HDi fuel rail broken

Post by Vojta15 »

Changing the rail did not help. The new return leakage pipes were faulty, I purchased the original part and it's fixed now!
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CitroJim
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Re: C5 X7 120 kW 2.0 HDi fuel rail broken

Post by CitroJim »

Pleased all is now good :D
Jim

Runner, cyclist, time triallist, duathlete, Citroen AX fan and the CCC Citroenian 'From A to Z' Columnist...