306 hdi broken :(

[Ben hdi306]

Is there sensors on the fuel lines any were?
Been messing about with the car and if I put live feed on the pump it starts for 3 seconds then dies am getting a tiny little bit of power but not enuff for it to work though the plug to the pump so I was thinking maybe there's a señor that on the rail or summin thats not doing its job by not telling the ecu to send more fuel? What do you guys think?

[C2K]

When you say you've been pulling at it for ages i'm sure it's bolted on. I can only remember the arrangement on the Rallye not the HDi but it's behind the battery normally.

LP pump runs all the time, there are no sensors with the specific intention to tell it to run, the excess is just returned back to the tank.

[Ben hdi306]

I was on about the green plugs in the black chase managed to get them out tryed diffrent ones still no diffrents really don't no what to do now

[cully]

you need to get it on PP and read live data regarding fuel pressure,
if you are not getting the cranking fuel pressure of 400bar the engine will not atempt to start

this could be cause by a few things
double brown relay
LP fuel pump
fuel filter
HP fuel pump
Pressure reg on pump
fuel rail sensor
fuel injectors

[Ben hdi306]

I've tryed a brand new brown relay still no diffrents lp pump works if I run a live to it.
How do I check the pressure on the fuel system do I need a sertain tool?

[cully]

you need to get it on PP and read live data regarding fuel pressure,
if you are not getting the cranking fuel pressure of 400bar the engine will not atempt to start

this could be cause by a few things
double brown relay
LP fuel pump
fuel filter
HP fuel pump
Pressure reg on pump
fuel rail sensor
fuel injectors

PP = peugeot Planet 2000 diagnostic software/equipment
or something that can read the info from the ECU cheap readers wont do the job

[charli_lady]

It's 280 bar to achieve a fire if memory serves, definitely not over 300 as mine don't make that much before they fire.

And yeah i think the relay is bolted in place, 1x10mm nut at the top iirc.

You can use a multimeter to check cranking pressure, should be seeing ~1.3v.

[Poodle]

Oh yeah, that ^^^ was me, hahah.

I meant to add: From what you've said it sounds like your lift pump is dying, try and find someone local with one they can temporarily swap for yours - if it works again you've found your culprit.

[Mr Whippy]

Exactly.

If in doubt, check with a known good item. Worst case it doesn't fix it sell as 'as good as new' at £10 off.

Tank pump is a very common fault so would be the best first port of call to check.


Dave

[Ben hdi306]

But it still works if I run a live to it dose that not count?

[cully]

it might run but is it pumping fuel!
The pumps eat there impeller blades hence the gold flakes in the filter housing

[Ben hdi306]

A big thank you to poodle(Alex) off the forums for coming over and helping me we may have found the problem the wires that run to the pump in the boot are damaged some were so can any one tell me were do they start from. and what way do they run.

I am thinking they run under the car but were do they start any one know?

[vincent1]

maybe from the brown relay plug which may give live to the pump? is the other just a earth? not got a hdi how many wires go to the pump motor?
so in theory if the wires got a break in it from the relay to the lift pump that could be your problem

[Poodle]

Glad to help bud, was good to see it running.

For anyone else reading this thread (or not, as the case may be ), the car runs fine when we put a live to the pump, the brown relay has been replaced as detailed in the OP and the plugs are all good, so it looks like it's a wiring issue. I'm about to shoot out and have a look now ben, will call in a bit.

[Ben hdi306]

Only reading 6.23 volts at fuel pump in tank dose any one know what way the wires run so I can check for breakages.

[C2K]

I'm confused, it was repeatedly mentioned that a live was put to the pump, top of this page said it only ran for 3 secs like that so what's changed between then and now?

As for the wires you could've followed them in the time you've been chasing for answers on here!

[Ben hdi306]

I could not get a good enuff connection to the pump so as soon as it started it came lose since then poodle/Alex came down changed a few sensors and I managed to hold the live on while he started it and it run for a while.


As for follow the wires I've found some that run down next the the tank but they are a diffrent colours and only put out 0.15 volts when turning the car on were as am getting 6.23 volts at the plug when turning the car on.
So instead of me removing the tank I wonted to know if any one has removed there tank and know what way the wires run.

[Ben hdi306]

just an update the wires run back through the body under the Capet lol followed them all the way up to the dash voltage was still the same so I got fed up and linked a new live with a fuse in the middle and wired it up to the ignition so when I switch the car on pump come on, car runs fine just been up and down the motorway done about 15miles every thing seems fine

If any one thinks this is a bad idea could you please let me know why, due to be being no expert.

[cully]

fuel being pumped onto a fire when the engine has stopped in an accident!

the ecu will shut down the pump when the engine dont require fuel you wont get this safegarde if you hotwire the pump

[C2K]

Glad that it is working but you ought to find the original wiring, probably a chafed/broken wire near the ECU.

[Mr Whippy]

Yep, deffo worth fixing it properly.

Now you know what was at fault it shouldn't be that bad to fix, just be methodical and work your way along

Might be a ball ache but as said above, in the event of something bad happening then it's nice to know things designed to keep you safe will work!

Dave

[Ben hdi306]

This will be a temp fix untill I find the fualt then looks like am going to be taking the dash up to see we're the wires run I've follows them up to the passage side footwell were there is a another connector plug then it gose behide the dash, still only getting 6 volts there for the first 10 seconds of priming time

[Poodle]

If it's managing to still supply some voltage i would assume that means a general degradation of the wiring, if it was a break it would show all or nothing, no?

[cully]

check the plug on the bottom of the fuel cut off these burn up too

[Poodle]

Can't find my wiring diagram, is the order of connection: ecu -> brown relay -> cut-off switch -> lp pump..?