Ford Fiesta (1995 - 1999) - 99 1.25 Temperamental Fuel Pump

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Wed 13 Jan 2010 18:30
99 1.25 Temperamental Fuel Pump - harry1
Oh dear, this is a long story ... and I live in Portugal, just in case it makes a difference ... e.g. to the model.

A few weeks ago, my car wouldn't start after filling up with fuel ... electrics all fine, turning over fine ... and then after a few tries it fired and off we went.

Same thing happened a couple of days later but this time it didn't start at all. It was a Sat am, so got it taken to a quick repair type place who diagnosed a broken fuel pump. This fitted as the car seemed "quiet" when turning on the ignition ... i.e. you coudn't hear the normal humm of the fuel pump working.

They had to order the part which took a few days, then installed it. All seemed fine. But immediately after picking up the car, the same thing happened again. The mechanic came, tried a few times and it worked. he said there was a problem with the igniton barrel ... which was admittedly very sticky, possibly because of a worn key.

The car worked fine for a few days and then the same thing happened again and I couldn't get it to go at all. The mechanics from the same garage came out, checked everything (fuses relays etc) and suddenly it started working again. They said they didn't do anything, and that the problem was to do with the ignition key barrel.

It is clearly to do with the fuel pump because the absence of a sound from the fuel pump when turning on the ignition is so noticeable.

Worried that it might happen again I went to Ford who were reluctant to say what it could be without seeing it but mentioned the key, the "fuel pump module" and the possible need to reprogramme the fuel pump. I booked the car in for a week later.

When I got home I tried my spare key which turned in the lock much more smoothly and all seemed fine so I cancelled the Ford appointment .... until a couple of days later (just before New Year's Eve) when the car wouldn't start at all ... also after filling up with fuel. Even my son bouncing up and down on the back seat above the fuel tank (which had worked before) could not coax the fuel pump into life.

A local garage said they would look at it after the New Year break and after several hours of looking and removing the fuel tank to get at the pump (during which they did confirm that a new fuel pump had been fitted) they located a connecting plug near the fuel pump which was burned out and had a melted wire. They replaced this and the car has been working fine for the past week.

Until today: twice it has behaved in exactly the same way, but fortunately started in the end. One of the occasions was after putting in some fuel. I am now very concerned that it is going to leave me in the lurch again and am wondering whether anyone has experinece of this sort of problem and/or suggestions about what it might be?

The odd thing about it is that the car has never stopped while actually running ... it just won't work from starting ... is it possible that it is to do with the keys/coding etc after all? Is there a direct link from the ignition to the fuel pump ... because all the other electrics are working fine.

Any thoughts gratefully received ...
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Wed 13 Jan 2010 19:59
99 1.25 Temperamental Fuel Pump - bell boy
trying to get my head round the fact the pump isnt under the back seat squab
anyway
was the replacement pump a new one?
melted wires would point to a pump on its last legs pulling too many amps
if wrong pump fitted there is a good possibility it could also burn out and or not supply the engine with enough fuel
is there a dent in the fuel tank?
is the guage lying and your tank nearly empty of fuel
have you tried brimming the tank and seeing what happens
i had this problem a few months ago trying to fit a 1.4 litre pump to a 1.0 litre corsa,weirdly it didnt supply enough pressure
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Wed 13 Jan 2010 20:54
99 1.25 Temperamental Fuel Pump - harry1
Hi ... thanks for this ...

Under the back seat there is a wire going into a rubber grommet but the garage that did the second repair said that they had to remove the petrol tank to get to the fuel pump ... shiould this not be necessary?

As far as I know the pump was new ... and when it works, it works fine, and sounds fine ...

That could well be the explanation for the melted wire as .. the car has done 174000 km.

I don't think it's a problem of the tank not having enough fuel because it happened today right after I put some fuel in!

Can you tell me what brimming the tank would do? Hen't looked for a dent --- what would that mean?

Thanks

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Thu 14 Jan 2010 20:21
99 1.25 Temperamental Fuel Pump - harry1
I can see that my chapter of woe has probably proved too long a story ...

Perhaps I should reduce it to one question: if all the electrics are working perfectly, including the starter motor, is there any way that a fuel pump can be affected by the key coding, condition of the ignition key barrel etc.? From my admittedly outdated understanding of vehicle electrics it would seem logical that, if power is reaching the starter motor then it should also be reaching the fuel pump, and that if the fuel pump is not working then the problem must be located somewhere in the electrics between the fuse box and the pump itself ... does that sound right?

Thanks in anticipation of any suggestions: it happened again today, and I am permanently afraid it will not start at all!
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Thu 14 Jan 2010 20:38
99 1.25 Temperamental Fuel Pump - billaboard
This might or might not be relevant. We have a '96 1.1 Fiesta, and it often just dies. The problem is with the fuseholder assembly and the specific fuse mounting that feeds the fuel pump. On our car this is just beside the steering wheel, and pushing the fuse about a bit makes it work fine until the next time. You can hear the pump running when contact is made.

I keep meaning to get this fixed - there are spare fuse holders in the assembly so it ought to be easy to link across.
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Thu 14 Jan 2010 21:12
99 1.25 Temperamental Fuel Pump - harry1
Thank you for the suggestion. This is exactly the sort of thing that I thought it might be because of the intermittent nature of the problem ... I have tried wiggling the fuses around a bit before and it didn't make any difference, but i think there are actually two fuse boxes on this model ... I'll check it out in daylight and will let you know how I get on.
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Thu 14 Jan 2010 21:37
99 1.25 Temperamental Fuel Pump - elekie&a/c doctor
The fuel injection system fitted to these is generally reliable.However the fault with the poor/overheated connection to the pump is a common issue that also affects Escort models.Has a new connector been fitted or was it just cleaned up and re-fitted?Also if the problem was ignition switch/immobliser related,then I think you would see an indication by the led by the side of the clock flashing quickly.May be worth checking the contacts to the fuel pump relay and fuse in the engine bay fuse box.When the car is in a non start condition,you need to verify that it is actually the fuel pump that is not working or something else;ie no spark.One possible idea to try to assess the fault ,is to wire a test light into the fuel pump wire where it runs under the seat.You will then be able to monitor any lack of power to the pump if and when it occurs.hth
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Thu 14 Jan 2010 22:17
99 1.25 Temperamental Fuel Pump - harry1
Thanks very much for your detailed comments. No, a new connector was not fitted ... because the garage didn't have one, but they said they used a part from another car ... could that make a difference?

I'm pretty sure that when the car doesn't start the problem is to do with the fuel pump because I know exactly what it should sound like when it is working!

I'm not sure I have the expertise (though I would have done a decade or two ago!) to mess around with the wiring, but thanks for the tip ...

Can I check the condition of the connector from the top (i.e. under the seat) or do you have to get to it by removing the fuel tank?

Can I ask you something as you obviously know what you are talking about ... in your experience could a faulty ignition switch etc affect only the fuel pump and nothing else? That is what seems so odd to me about this as a possible explanation ...

Thanks a lot for your help.
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Thu 14 Jan 2010 22:31
99 1.25 Temperamental Fuel Pump - elekie&a/c doctor
A s/hand connector should be ok if it is good condition.Inspection of this connector is a little tricky because the access hole under the rear seat is not directly above the fuel pump.So it is either drop the tank or cut away some of the metalwork under the seat to expose the wiring.Ignition switches rarely give trouble on these and there is no dedicated pump cicuit from the switch,so a swtch fault would cause other circuits to fail as well.One other item that has not been mentioned,is the fuel shut off/crash switch in footwell(passenger side ,if i recall).I have seen one of these give erratic starting problems.This is easily by-passed for test purposes by bridging the 2 wires together.hth
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Thu 14 Jan 2010 23:15
99 1.25 Temperamental Fuel Pump - harry1
Thanks for all of this ... very helpful. I did wonder about the fuel shut off switch as being a possible source of the problem ... if I can find out how to get to the terminals on it I shall give it a try next time the problem arises.
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Fri 15 Jan 2010 11:35
99 1.25 Temperamental Fuel Pump - bell boy
ive never had a problem with the switches they are well built
however the burn contacts in the pump feed is a very good point it could also be the answer and maybe you have a bad earth feed return due to all the heat build up
cutting the rear floor is also good advice (within reason obviously) and is what i do in similar circumstances rather than removing tanks
maybe a good idea to earth it onto the floor pan
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Sat 16 Jan 2010 09:48
99 1.25 Temperamental Fuel Pump - harry1
Hi everyone ... thanks for all your help and contributions. The problem happened again yesterday. Fortunately we were on our way to tell the garage about it and it wouldn't start right outside their premises. So they took it all to bits again and it was still a problem with the connector. They had replaced one of the terminals but not the other two. They have now fitted three new terminals and we hope it is not going to let us down again. If only the connector was accessible, it's the sort of thing you could easily do yourself ...
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Thu 5 Jan 2012 14:12
99 1.25 Temperamental Fuel Pump - chrisfiesta

Hi there,

I had the same problem. I had a choice to drop the tank and check the connections to thye fuel pump or hire a 4.5 inch angle grinder and cut a hole big enough in the panel under the back seat to gain access to the wires. I chose the grinder !

Th 12 volt wire (violet and orange) had burnt out ! I snipped off the connector and re crimped the wires with the correct size conectors and then wrapped insulation tape around them. it worked like a dream.

Just be careful not to nick the fuel pipe with the angle grinder like did. i had to fix that afterwards too :-)

Any other problems please message me and i will see if i can help, i have extensive experience with Fiesta's.

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Sat 18 Jun 2016 14:05
99 1.25 Temperamental Fuel Pump - jeffwalker

the fuel pump fuses have started to blow as soon as the engine is started

ran out of 10amp so used a 20amp to get home and the car ran fine but fuel pump buzzing loudly is this signs of a knackered pump

I tried chopping into the thick black wire assuming it was the earth to bodywork and re-earthed to bodywork but made no difference so about to open up hole near the pump with a dremel and inspect.... any clues

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Sun 19 Jun 2016 11:39
99 1.25 Temperamental Fuel Pump - jeffwalker

i`m having the same problem my fiesta keeps blowing fuses

went through a whole packet of 10 amp ones

in an emergency I used a 20amp one and the car ran fine except the fuel pump was really loud....any clues before I reach for a dremel?

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Sun 19 Jun 2016 12:00
99 1.25 Temperamental Fuel Pump - elekie&a/c doctor

Yes ,the pump is goosed.When replacing it,make sure you get the correct type.There are at least 3 different varieties.Also not a good idea to increase the fuse value to double.You may get away with it temporarily on an old car like this.but on a modern car the wiring will burn before the fuse blows.

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Thu 20 Jun 2019 11:00
99 1.25 Temperamental Fuel Pump - TimCar

Hi

I have access to the fuel pump via a cut out in the seat. Is it easy to replace the connectors? If I buy them online are they called fuel pump connectors? How much do you think a garage would charge for this job?

Many thanks

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