Fuel problems with my '03 75 Cdti tourer.
 

Hi Guys.

I'm currently having a problem with my '03 tourer with 76000 on the clock. I allowed her to run a little low on fuel last week and since then she just refuses to start.

She won't start at all when cold except with easy start but will occasionally when hot, with lots and lots of cranking, once again easy-start produces instant starts.

Once started she runs as well as ever with no hesitation or stalling and will rev freely up to the redline with no sign of misfire.

I've tried nipping the injector return pipes and get no sprayback, this makes no difference to the non-starting either.

I can hear both fuel pumps running and have changed the fuel filter; however, if I disconnect the under-bonnet pump the car won't start and run at all, even with easy start. Disconnecting the in tank pump makes absolutely no difference, it will start with easy-start and run as normal.

Before running off to my local injector centre "costapacket motors", I would value the opinions of you wise ones. I now strongly suspect that the problem is with the in-tank pump and lean strongly towards replacing this as my next port of call. Is this advisable or would you go to "costapacket" for the diagnosis first?

If replacement is recommended, I intend to go down the peugeot route as posted by Efreeti but I can't seem to be able to contact Simon for the photo's; does anyone have the PDF file or know how I can obtain it?

-John.

Have you done the leak off test? someone on here did a "how to" but can't seem to find it at the moment

Yes Alan, I did the leak off test but it still wouldn't start.

-John

Hi,John

If you can lead some electric measurements;
there are two important informations.

1 Low pressure fuel sensor (fuel filter housing):
for 2.6 bars,you must have about 4 volts on the yellow/blue wire

(sensor disconnected,engine can start)


2 Fuel rail pressure sensor(at the end of the fuel rail)
(blue/black wire)
you have:1.3 volts at idle and 2 volts at 3000 rpm.

(sensor disconnected,one can start the engine too)


And don't forget ;during cranking,the tachometer move slighty
(Showing crankshaft sensor is OK)

Mike

Ok thanks Mike. I'll get my multimeter out tomorrow and try this.

I assume that the crankshaft sensor is ok because it runs perfectly after starting with easy-start, surely it wouldn't if this sensor was faulty?

You are right,John

But it could be useful to remember :}


Mike

I too the voltage readings which were only slightly different to those which you have suggested Mike. The fuel sensor gives me 5.68 volts with the engine idling and the fuel rail sensor gives me 1.28 volts at idle and 2.12 volts at 3000rpm.

Are these differences significant?

-John.

John,
Concerning the the rail sensor,it seems correct but 5.68 volt for the low pressure ,it is just impossible because it is supplied with a 5 volts from the ECM
(black/purple wire)

(No need to have the engine running)

When my intank pump died,startings were more difficult and there was a kind of gurgling
coming from the UBP

Last Possibilities are: ECU Capacitors, Injector Leakback.

Mike

Sorry Mike, I'm getting a little confused.:confused:

I checked the voltage on the yellow/blue wire on the fuel filter housing and got the 5.68 volts, I've checked it again and still get the same reading.

The other readings (1.28V & 2.12V) were taken from the blue/black wire at the end of the fuel rail.

:(Auto electrics have never been my strong point.:(

-John.

John,

May be the problem,
Disconnect the plug , key position 2,you must have 5 volts on the middle pin

(Purple/black) ;it come from the ECU.

The sensor send back a variable voltage from 0 to 5 volts on blue/yellow wire
representing the pressure.


I forgot,you can try this: (costs nothing)
Simply,get up the camsensor of 1 or two millimeter.

http://www.the75andztclub.co.uk/foru...ad.php?t=65916

You can also clean the rail pressure sensor contacts

Mike