C5 2.2 HDI Fuel pipe blowing off

Thompatruck · Unread post by **Thompatruck** » 18 Mar 2009, 15:01

I've had a read of the other recent similar problems but they don't seem to be the same. Friend's C5 is blowing the fuel pipe off the priming balloon and covering everything with fuel, done it twice now, last time over the mechanic

(he wasn't happy) any ideas what that'd be? Mechanic is stumped.

Should there be a clip on the pipe to lock it in place?

Thanks

Unread post by **CitroJim** » 18 Mar 2009, 19:09

Yes, I'd assume some sort of clip for such a critical pipe. Have a check of any fuel return lines back to the tank; could be a blockage leading to excessive back-pressure in the system.

Could the lift pump in the tank be delivering excessive pressure for some reason?

nick · Unread post by **nick** » 18 Mar 2009, 19:45

Sounds a bit odd this. Do you know the history of the car?
Normally an HDi will have either a Bosch fuel system with an electric lift pump in the tank, or a Siemens system without a separate lift pump and with a priming bulb in the fuel line.

If there's a priming bulb it sounds like a Siemens system, but on those the fuel line is under negative pressure, so the pipe shouldn't have any reason to burst off.

I wonder if someone has tried to fit the priming bulb from a Siemens system onto the Bosch system?

Either that or perhaps theyve mistakenly fitted an electric lift pump to a Siemens system which shouldn't have one? The wiring for an electric pump is there whether the car is supposed to have one or not, so its theoretically possible to fit an electric pump to a car that doesn't need one!

wheeler · Unread post by **wheeler** » 19 Mar 2009, 00:52

nick wrote: Either that or perhaps theyve mistakenly fitted an electric lift pump to a Siemens system which shouldn't have one? The wiring for an electric pump is there whether the car is supposed to have one or not, so its theoretically possible to fit an electric pump to a car that doesn't need one!

I would say that was spot on, If it is definitely a 2.2 then it will be a bosch system & should have the electric lift pump in the tank & no hand primer.

I would say its most likely a 2.0 with siemens system & has had a lift pump fitted in error, as nick says the wiring is there for the pump.

bencowell · Unread post by **bencowell** » 22 Mar 2009, 11:31

The 2006 2.2 HDI twin turbo 173's have hand primers!

nick · Unread post by **nick** » 23 Mar 2009, 06:52

Do they also have a lift pump though?
I may be wrong, but as far as I know no HDi had both a lift pump and a hand primer. There would be no need surely?

wheeler · Unread post by **wheeler** » 23 Mar 2009, 11:42

bencowell wrote:The 2006 2.2 HDI twin turbo 173's have hand primers!

Sorry, your right but i was assuming it's the old 2.2 with the bosch EDC15 injection system which has an electric lift pump & no hand primer.
You will have the Bosch EDC16-CP39 which has no electric lift pump in the tank therefore it has a hand primer.

nick wrote:I may be wrong, but as far as I know no HDi had both a lift pump and a hand primer. There would be no need surely?

Yes, I can't think of any HDi injection system that uses both, only one or the other.