I need to depressurise the fuel system to remove the fuel filter

i have been told to remove the fuel pump relay harness and the engine should die and the engine then should be depressurised

I have no clue where about this harness is

Any one have any ideas?

thanks

Edited 24 June, 200719 yr by ryda

i am trying to find out where the fuel pump relay .

I cant even find my hayes manual to see if its listed in there

If anyone has any clue of where it is located it would be greatly appricated.

thanks

I wouldnt bother even trying that, just remove the fuel filter.

fuel pump relay is in the engine bay next to the ecu, top right hand corner of the engine bay near the fuse box.

as for depressurising the system, i just normally let a union off very slowly and its fine. i doubt there will be much pressure just sat in the line tbh

I was going to say that, when I changed my TB I just cracked off a union slowly with a rag under it. Wasn't sure whether it was any different on the mpi's though!

surely pulling the fuel pump relay out would just have the same effect as turning the ignition off? sounds like a waste of time to me like

If the pump isn't running but the ignition is, then in theory any extra pressure in the lines would be injected and burnt? But I doubt it's gonna make much difference either.

i dont think the lines themself would hold that much pressure anyway without the pump running!

if you take the relay out then the injectors wont work anyway. THe lines wont be pressurised unless you've only just switched off the engine. Even so, some fuel is going to come out no matter what you do so have some rags and an old tub or something to catch the fuel in.

whats a union

A union is a pipe joint. As in 1 of the above, remove the fuel pump relay then try starting the engine. It may fire but not for long. Its then depressurised.

Maybe I'm mistaken but i thought the filter was before the inline pump anyway

no its after the pump ,to depresureise the system pull the fuse for the pump at the fuse box and start the engine and leave running untill it cuts out,then the system as been depresureised but be warned there will be some spilage still when you undo the pipes but it wont spray every where just drip.

I've changed the fuel filter a few times, changed the inline pump, and the in tank one and have never 'depressurised'. do what optima said just change it. there is hardly any presure anyway when the engines off as pinches has already said. doing anything else is a waste of time.

Agreed - just be ready with a rag - best way to change the fuel filter is to take one end off the old one - and immediately attach it to the new one - then do the same on the other end. Then re-attach it with the body clamp. Job done.

I never did it on my car when changing the filter.

Just make sure you that when you re-start the car after the work, turn the ignition on a few times to prime the pump and therefore get fuel into the filter. Should avoid any initial spluttering problems.

Good luck.

Iv taken a few images of the area around the fuse box, can somebody please spot out the fuel pump relay

fuse box

fuse box 2

fuse box 3

3

you dont need to depresurise honest.

Removed the fuel lift pump hoses from my car the other day.. tiny bit of petrol leaked - a couple of drops, but that was it!

If you prime the pump, obviously a bit shoots out! There is sod all pressure in the system when the car is cold as far as I can tell aswell.

i managed to do it perfectly, took about 15mins

thanks for you help everone

Edited 27 June, 200719 yr by ryda