Hi everyone,
I am looking for some help with my 2013 Citroën C5 X7 2.0 HDi RHH.
The fuel system keeps getting air into it. After the car has been standing, it can become difficult to start, and I need to use the manual fuel priming pump to remove the air and fill the system with fuel again.
So far, we have replaced the following parts:
Fuel filter housing cover
Manual fuel priming pump
Fuel filter
Fuel filter housing seal
Fuel filter housing screws
Plastic drain screw on the fuel filter housing
Plastic bleed screw on the fuel filter housing
Some of the original fuel connecting pipes are no longer available to buy, so I replaced them with standard fuel hose with an 8 mm internal diameter. I secured the hoses with hose clamps.
Unfortunately, the problem is still present, and air is still entering the fuel system. There are no obvious external fuel leaks that we can see.
Where else could the system be drawing in air? Could the problem be caused by the replacement 8 mm fuel hoses or the hose clamps, the quick-connect fittings, the injector leak-off pipes, the complete fuel filter housing, or something near the fuel tank?
Has anyone experienced a similar problem on the 2.0 HDi RHH engine? What would be the best way to find the exact location of the air leak?
Any advice would be greatly appreciated. Thank you!
Thomas
Citroën C5 X7 2.0 HDi fuel system keeps getting air in it
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KomarTom
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mickthemaverick
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Re: Citroën C5 X7 2.0 HDi fuel system keeps getting air in it
I would check the fuel lines right back to the tank, you may have an issue along there. 
I used to be indecisive, now I'm not so sure!
I used to ride on two wheels, but now I need all four!
I used to ride on two wheels, but now I need all four!
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Peter.N.
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Re: Citroën C5 X7 2.0 HDi fuel system keeps getting air in it
If you have a bit of clear fuel line before the filter, are there bubbles in it when you pump it up, just so that you can determine whether it is getting in before or after the the filter.
My first x7 had this problem, I changed the filter housing and all the pipe on the engine and it still did it. I even changed the HP pump and it wasn't that either, I scrapped it in the end.
But a couple more things to try, if you can park it facing down a fairly steep hill so the fuel tank is above the engine and leave it for a while it should show a leak where air is getting in. I believe also if you have a leak in the injector return pipes, air can get in that way. Mine was a long time ago but I seem to remember that the leak off circuit goes back to the pump. The non return valve in the primer bulb should stop it flowing back to the tank which is what seems to be happening so if you have a small length of clear plastic pipe before and after the filter that should show you where abouts the leak is.
As a final remedy you could fit a small electric pump in the line before the filter. I never did find what the problem was and I still have the car here in the field, I hope you find the problem with yours. Is it better parked facing down hill?
Peter
My first x7 had this problem, I changed the filter housing and all the pipe on the engine and it still did it. I even changed the HP pump and it wasn't that either, I scrapped it in the end.
But a couple more things to try, if you can park it facing down a fairly steep hill so the fuel tank is above the engine and leave it for a while it should show a leak where air is getting in. I believe also if you have a leak in the injector return pipes, air can get in that way. Mine was a long time ago but I seem to remember that the leak off circuit goes back to the pump. The non return valve in the primer bulb should stop it flowing back to the tank which is what seems to be happening so if you have a small length of clear plastic pipe before and after the filter that should show you where abouts the leak is.
As a final remedy you could fit a small electric pump in the line before the filter. I never did find what the problem was and I still have the car here in the field, I hope you find the problem with yours. Is it better parked facing down hill?
Peter