2001 C5 2.2HDi

corsehf · Post by **corsehf** » 10 Oct 2010, 22:52

Hello all,
I had an issue the other day when my C5 just suddenly stopped whilst doing around 70 on a dual carriageway.

No idea why so i opened the tailgate to get at my tools only to find the tailgate actually dripping in diesel!!

I opened the bonnet to find a similar state and everything covered in diesel.
On removing the engine covers, i found that the 2 fuel pipes that run to and from the centre of the fuel filter housing (top) had come off??

Has anybody else ever seen this before as i have not and i have been watching and checking on a daily basis but i cannot even pull them off.

Total mystery unless someone knows better??

KevMayer · Post by **KevMayer** » 10 Oct 2010, 23:05

Blimey, this is a puzzle and worry.

Quite often what is reported here on the 2.2 Hdi usually happens to my 2.2 before long, so, it will be good to find out what happened.

It sounds like the pipes have been subjected to quite a bit of pressure.

I can't imagine how diesel got onto the tailgate of your estate.

Have any pipes come loose at the tank end?

corsehf · Post by **corsehf** » 10 Oct 2010, 23:17

The diesel reached the tailgate from under the car!!
I was losing so much diesel that it just run along the bottom of the car and up the tailgate.
Worryingly, I probably sprayed a few people/cars with diesel before the car stopped.

Post by **myglaren** » 11 Oct 2010, 06:42

Could the fuel return be blocked and sufficient pressure has built up to blow both lines off the filter?

c5cro · Post by **c5cro** » 11 Oct 2010, 12:32

I had a similar knocking noise on my C5(2004),and discovered that droplinks were making it so i replaced them and the noise disapeard.
I still have a problem with a noise from rear suspension when i drive over poor surface roads....its a bit difficult to describe...it sounds like something is in boot...The car is not hard or uncomfortable,,simply a bit noisy which spoiles the ride...

KevMayer · Post by **KevMayer** » 11 Oct 2010, 17:38

This could be due to a blocked 'return to fuel tank' pipe.

There are two types of fuel filter shown for the 2.2 Hdi, but, each arrangement has 3 connections.

1. Fuel feed to filter from low pressure pump in fuel tank
2. Fuel feed from filter to high pressure pump
3. Return from filter to fuel tank.

The 'return to fuel tank' pipe picks up return fuel from the filter (3. above), leak off fuel from the injectors and return fuel from the high pressure pump pressure regulator.

So, if the 'return to fuel tank' pipe became blocked then the fuel filter and local piping would quickly over pressurize.

There's a fuel cooler in the return pipe which is found under the car under the floor at the rear seat area. Has this had a knock which has obstructed the return flow?

cachaciero · Post by **cachaciero** » 11 Oct 2010, 22:13

Yes! I can shamefacedly put my hand up and say I have had a similar incident.
Why shamefacedly? well having had the filter apart for some reason I failed to ensure that the pipes were fully "clicked home" on replacement, took about 600 miles before the pressure finally separated them with much diesel sprayed around the engine compartment before the engine stopped thus forcing me to look under the bonnet

cachaciero