Very frustrating fuel leak... (Fixed)

[pgascoyne]

Well I know I've got a fuel leak, the damn driveway keeps telling me!
I know it's not brake fluid(no loss according the level marks), power steering fluid(no loss according the level marks and pinky/red colour) or coolant(bright orange/pink) due to it being green.
So the last weekend or two I've been trying to isolate it.
Basically the top of the engine is dry but the sump/cross-member are saturated with diesel.
So today I decided to get the car on axle stands, remove the covers and have a good look, nothing really stood out so I cleaned everywhere that was wet and then put everything back together and go for a blast down the motorway and back and see what I could find.
Well on taking the covers off again the sump was soaking wet, as well as many other areas. Initially I thought it might be the fuel cooler under the drivers floor pan as that looked wet but couldn't figure how fuel would get to the front of the engine with the wind against it. So ruled that out.
So I cleaned everything up again(didn't put covers back on) and then just went 100yds down the road hitting 3-4k revs and returned and again the sump was drenched in fuel.
So now I'm looking everywhere and damn if I can find the leak!
The fuel hoses all look dry, the fuel filter housing is dry and the fuel lines from the cooler to the filter also look fine. The gearbox side is dry as a bone as it should be.
It's not the high pressure side as that would shoot fuel top side, so I'm suspecting the low pressure side but where on the front of the engine would it be that's below the filter housing unit?
It does seem as though it coming from the AC compressor area as that gets soaked every time.
The most annoying thing is I can rev like crazy stationary but nothing leaks, it's not until I drive it that diesel leaks everywhere...
Anyone got any ideas or thoughts?

[StevieboyTD]

You say it's defo not PS fluid, just check the hose clip on the top of the PS pump, mine was pissing out of there and i was sure it was fuel until i actually saw it weeping.

[Doggy]

Guessing you've eliminated the drain valve on the fuel filter housing?

An HP leak in the area of the pump / fuel rail might fit the bill. Your idling pressure will be about 250 Bar, but you get up to 1350 Bar when it's working hard. I doubt you can get above about 500 Bar by revving it up while stationary, so it may not show.

[mjb]

Sounds a lot like a pas fluid leak. On mine (V6), the high pressure line from the pump goes across the front of the engine then down the front of the gearbox bell housing. I had a small leak round there (where a solid bit of pipe joined a flexible bit) which sprayed the whole area underneath with a green/yellow liquid despite the stuff in the reservoir being red.

[hammerman]

Sounds exacly like my diesel leak.All fixed now though.viewtopic.php?f=1&t=12208&p=162202#p162202

[pgascoyne]

Thanks for the replies guys, I will investigate further when I get a chance which won't be until Sat.
Will report back when I've found the culprit!

[pgascoyne]

Finally found out where the leak was coming from.
Thanks to hammerman's post I found mine was coming not from the injection pump electro valve, but simply from the union coupling of the output of the fuel pump to the fuel rail.
Just needed less than 1/4 turn to tighten it up.

Fuel Leak.jpg

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