Won't Start - Fuel Pump?

[regdorpten]

Foolishly ran my petrol tank to empty last night....so empty I had to walk to the local petrol station to fill a can with petrol.

Trouble is now the car won't start at all. It turns over, very occasionally catches briefly but won't start.

There's enough petrol in the car (abt five litres). It's not the battery (it's turning over) and it's definitely not the immobiliser.

As the engine sucked the last of the petrol out of the tank I heard a slight wine from the petrol tank....like the sound of the windscreen washer pump and I fear a fuel pump may have died. How many pumps does it have and where are they?

Any other ideas? Luckily the car's outside my house but it's not going anywhere...will probably have to call a mechanic out.

Matt

[robertxmb]

Sediment blocking filter in tank?

R.

[regdorpten]

Hi Robert, I haven't had a chance to check the filter, but isn't that likely to cause rough running rather total failure to start? There'd have to be a hell of a lot of sediment to black the fuel completely wouldn't there?

[noz]

The pump is in the tank. It forms part of the assembly which also contains the float for level indication. It also has a filter on the pickup. The filter is quite large so it would take a lot to block it.

The first thing to do is determine if the pump is running or not. Lift the back seat and remove the sound deadening above the tank access. It already has a cutout for the purpose. Put your ear to the part where the fuel pipes connect and turn on the ignition. Can you hear the pump? Now disconnect the fuel pipe in the engine bay and again turn on the ignition. Does fuel coome out of the pipe? It is conceivable that its airlocked. If so, disconnecting the fuel pipe in the engine bay should help clear the air.

Please let us know how you get on.

Cheers

noz

[regdorpten]

Thank-you Noz,

For an ignoramus like me can someone tell me where the fuel pipe is in the engine bay (and what it looks like?)

[citroenxm]

2.oi Turbo TCT,

The Fuel rail sits over the injectors in the Vecinity of the Spark Plugs - the Metal rail with a Round silver Pot like Item which is the fuel pressure regulator

There Two rubber hoses connected one to the regulator which IIRC is in the middle, and the other to the end of the Rail...

Can never remember which one is fuel in, and which is return.. I think the one to the regulator is return, so if you disconnect the other, if theres fuel in the rail under pressure it WILL start to Spray out!! WHAT YOUR EYES!

Paul

[regdorpten]

Thanks. Does anybody know if this car (1995 S2 petrol 2.0 TCT) has a fuel cut off switch which may have been tripped? If so where is it in the engine bay?

[robertxmb]

Can't answer the first part but if there is one it should be easy to identify. It is square rubber with a circular recessed "button" On mine it is plain black colour but I seem to recall that red features in some car models. On mine it is on driver's side of engine bay forward of the sphere. I think it unlikely that running out of petrol alone would trip it or cause component failure in the fuel line. Ok ,unlikely but not impossible! Airlock or choked filter seems more likely.

R.

[regdorpten]

OK. So first of all there is a very very quiet electrical hum coming from the pump when the ignition is turned on...so quiet you can only just hear it with ear pressed to the pump. I tried disconnecting the fuel pipes in the engine bay then turning the key. No fuel produced but there does appear to be a bit of a vapour haze at the mouth of the pipe which disappears when ignition is switched off (may be my imagination though). I then disconnected the pipes on top of the pump and turned the key. Again no fuel produced at this point.

So I unscrewed the pump nut, removed the pump and had a look...nothing outwardly problematic. No residue inside or out of the teabag mesh on the bottom, no dirt in the tank, clean petrol, etc

Finally I tried turning the car over with the pump connected but out of the hole. Again no sound or sign of life.

The fuel level indicator is however working and inasmuch as it draws its electrical current from the same pump am I therefore right to assume the fault with the pump is not due to a connection under the LHM tank?

I had assumed the teabag on the bottom of the pump assembly was the fuel filter but i've just consulted the haynes manaul which says it's under the car, which has to be jacked up...will have a look at that when I get a chance but to my mind it looks like the pump may have burnt out while the tank was empty. I do remember quite a loud whine coming from the pump as the engine drained the last of the petrol the last timeit was running.

A quick browse on ebay shows new S1 fuel pumps for £25 and S2 ones for £300?!

[dean]

Hi

Firstly i must say there is no difference in the MK 1 and " pumps between G reg and N reg at least as they are all the same, pressure is regulated on the return from the fuel rail as Paul says too, so that has nothing to do with the pump, you can buy new motors and fit them to your pump ass very easily and its much cheaper BUT i am sure the Fuel pump relay is under the front cover of the ecu cover in the engine bay, i pop the cover off of the relay and operate the relay manualy or bridge the thick yellow wires in the relay plug, this will tell you if the fuel pump or relay is at fault before you jump in and buy a new pump.

Good luck

D

[regdorpten]

I have attached (hopefully) a photo of the gubbins under the ECU front cover. Which of this lot relates to the fuel pump and how to I get poeer to the pump manually to see if it's working?

[dean]

Hi

Ok now you are testing my memory , I think that the Fuel pump feed would come from the double relay (brown) which also serves the ignition and that the purple relay feeds the clutch on the A/C compressor, the trouble is you cannot just pop the top off of the double relay and manualy trigger it so you will need to know the pinouts for the plug.
The easiest way in this case would be to supply power directly to the pumps multi plug under the rear seat though, if this fails and the pump is at fault i do have a couple of spare fuel pumps, second hand of course but working.

D

[regdorpten]

To be honest I think the easiest way would be to buy one of those pumps off you if you have one spare. The PM and email functions on the site don't seem to work (at least no for me). Could you email me at regdorpten@yahoo.com?

[regdorpten]

It was indeed a faulty pump, now replaced with a secondhand one. A warning never to let your tank run dry...it burnt out the pump.

Once you get the retaining nut off it's a very easy switchover. But you have to be careful to make sure you put it back on very tightly with the seal firmly in place because when you fill up the petrol goes right to the top. I was rewarded with the alarming sight of petrol flooding over the station forecourt when it leaked out of the pump aperture. The nut was only finger tight, and it wasn't enough so I tapped it around with a hammer and chisel.

Does anybody know why the arrows on the nut and and pump assembly have to be lined up? I've tightened mine as much as possible and it doesn't seem to be leaking anymore, but the arrows are still about an inch out of alignment. I could I suppose just unscrew the nut and then twist the pump around a bit to meet the final resting place of the nut, but am worried that may restrict movement of the petrol indicator float.