Xsara 2.0 hdi fuel pump problems

Paulinderjia · Post by **Paulinderjia** » 31 Jul 2009, 09:27

Hi everyone.
I am hoping that someone here might be able to help.
I have had an intermittant problem with my 2001 xsara for around 6 months now. What happens is that i will go out to start the car and when i turn on the ignition, you don't hear the normal buzz from the fuel pump and the vehicle will not start. After various tests i decided to replace the fuel pump relay(the brown relay that sits on the bulkhead with the red clip). I thought this had cured it but the problem came back.
I have since found that when i get no sound from the pump and the car won't start, all i need to do is run a wire from the positive on the battery to the 15amp fuel pump fuse in the fuse box & the pump cuts in & the car starts. I remove the wire and everything can be ok for a few weeks. Then for no apparent reason it will do it again a few weeks down the line. The problem is it seems to be getting more frequent, so i am starting to think i have a major problem.
Any help would be much appreciated
Thanks
Paul

citroenxm · Post by **citroenxm** » 31 Jul 2009, 10:17

Hi and welcome!

Sounds like POSSIBLY more like a break in the feed wire you are bridging...

Have you had a replacement fuel pump (in the tank) fitted?? They can play up giving your simptoms... but it seems you solve it with your jumper wire

Citroen wiring can have a habit of breaking up inside the insulation.. causing problems like yurs..

Regards
Paul

wheeler · Post by **wheeler** » 31 Jul 2009, 10:31

Most likely one of the interconnectors behind the ECU causing the problem.
See here > http://www.frenchcarforum.co.uk/forum/v ... +connector

Paulinderjia · Post by **Paulinderjia** » 31 Jul 2009, 10:56

Well i didn't expect a reply so quickly. I had a new pump fitted 18 months ago and when checked with a meter there is always power there. I will look at the two interconnectors behind the ecu..(if i can find them) and let you know what happens.

Thanks for your help both

Paul

wheeler · Post by **wheeler** » 31 Jul 2009, 23:12

Paulinderjia wrote:Well i didn't expect a reply so quickly. I had a new pump fitted 18 months ago and when checked with a meter there is always power there. I will look at the two interconnectors behind the ecu..(if i can find them) and let you know what happens.

Thanks for your help both

Paul

Check the power feed with a proper 12v fillament bulb test light, not a multimeter or LED test light, it can still show 12v/light the LED but not enough current to light the bulb or power the fuel pump.

Post by **Paul-R** » 01 Aug 2009, 10:56

We had a problem with the Xsara a few months after we got it about 4 years ago. If the car was stopped then sometimes it wouldn't start immediately afterwards. There didn't seem to be any reason why and it would usually start after a few tries or leaving it for an hour or so.

First of all I suspected the inertia switch and presssed the button. I eventually bypassed it (it's still bypassed!) and that seemed to cure it for a short while but then it would do it again.

The worst time was when we took it to France on holiday. It behaved impeccably for a couple of weeks and then, after our last night in France, refused to start in the morning. At first I thought it might have been low fuel level but after 5 1/2 mile trips with the 5l fuel can to top the tank up it still wouldn't start so I gave up and called the RAC. About an hour later the recovery man turned up and the first thing he did was to turn the ignition key. Of course it started for him and with much embarassment we were on our way. There were several more switch-offs before we got home that day but it always restarted.

Back home I started investigating. I posted my questions and results on the then What Diesel web site (now unfortunately gone) but as I remember it I only had the wiring diagram for the Phase I Xsara from the Haynes BOL to help me. Using my multimeter I quickly found that the fuel pump in the tank wasn't being given any voltage. This is supposed to be provided by a relay or two but wasn't. Furthermore, the voltage to the relay was low. Without a proper diagram I couldn't be sure where it was fed from but I strongly suspected the ECU. The voltage was being reduced from 12v to about 6v or 7v regardless of whether there was a load or not.

The only thing that can reduce voltage without a load is a semiconductor PN junction and the ECU is stuffed full of these. I never did find out what the problem was as I thought "stuff it" and arranged for a separate, ignition controlled feed to the pump through a fused relay (sourced from a Renault Espace).

It's been working like that 4 years without any problem. I suppose that strictly speaking I have lost the safety aspect that if the ignition is switched on WITHOUT starting the engine the supply to the pump switches off after 10 seconds or so but that's a price I'm well willing to pay.

A bit of a long post but I hope that something there will help you.