Diesel Fuel Pump Question

[Rick-sta]

Can anyone advise me on this.

Recently I've been experiencing a starting problem with the 75 Diesel. I've been advised that it may be due to the solenoids in the starter motor but haven't had a chance to take a proper look into this yet.

I've noticed that when the car is parked on a slant with the rear end higher than the front, it doesn't experience any starting issues. However, when it is parked with the front end higher than the back then it sometimes (not always) struggles to start. I have also just noticed that I cannot hear any buzzing noise from the fuel pump at the rear of the car when I turn the ignition (if there is one at the back on the facelifts I can't remember).

I haven't had a starting problem for over a week now but am wondering if its due to the rear fuel pump? I can hear a buzzing noise at the front of the car which I assume is the under bonnet fuel pump.

Would anyone be able to advise? Is there a way of knowing for sure if the fuel pump is working or not?

Much appreciated!
Rick

[1gp]

yep its looking like intank pump failed or failing. if your under bonnet pump is going at a right rate of knots, and noisey then its looking like itp.

[HarryM1BYT]

Open filler flap, remove cap, switch the ignition on and quickly put your ear to the filler. For several seconds you should be able to hear the ITP, if not it has failed.

The other, more certain way - is to disconnect the pipe feeding from the rear, to the UBP and see if diesel flows out of there, as but as above.

[Rick-sta]

Thanks for your replies - I'll have a look into this tomorrow.

In the case that the rear pump has gone, how long would it take roughly before it starts causing problems for the under bonnet fuel pump?

Is this a common issue with the diesels only, as my dad used to have a 1.8 non turbo and got just over 50k miles with no problems at all (just needed a cat replacement once).

cheers!
Rick

[3disco]

Originally Posted by Rick-sta

Thanks for your replies - I'll have a look into this tomorrow.

In the case that the rear pump has gone, how long would it take roughly before it starts causing problems for the under bonnet fuel pump?

Is this a common issue with the diesels only, as my dad used to have a 1.8 non turbo and got just over 50k miles with no problems at all (just needed a cat replacement once).

cheers!
Rick

I thought the facelifts only had a rear pump!

[HarryM1BYT]

Originally Posted by Rick-sta

In the case that the rear pump has gone, how long would it take roughly before it starts causing problems for the under bonnet fuel pump?

How long is a piece of string?

It depends on so many factors - how much life is left in the UBP, how hard it has to work, how much fuel you normally keep in the tank. Some manage years, some manage weeks.

[3disco]

Originally Posted by HarryM1BYT

How long is a piece of string?

It depends on so many factors - how much life is left in the UBP, how hard it has to work, how much fuel you normally keep in the tank. Some manage years, some manage weeks.

So would it have one?

[HarryM1BYT]

Originally Posted by 3disco

I thought the facelifts only had a rear pump!

Early facelifts had two pumps, some of the later ones had just the ITP.

If this car only has the ITP, then it would seems it might be intermittent so could fail completely at any moment.

[Rick-sta]

I have both the in tank pump and under bonnet pump (under bonnet is the one behind the fuel filter isn't it?). I'll have to check properly over xmas and hope the under bonnet lasts until the new year.

Thanks for the help

[HarryM1BYT]

Originally Posted by Rick-sta

I have both the in tank pump and under bonnet pump (under bonnet is the one behind the fuel filter isn't it?). I'll have to check properly over xmas and hope the under bonnet lasts until the new year.

Thanks for the help

Yes, the UBP is mounted on the firewall, rear of the battery. Fuel goes from ITP, to UBP, to the filter, then into the HP mechanical pump. surplus fuel is then returned back to the tank, via the cooling unit (mini radiator) at the rear.

A quick way to test for fuel flow, through the electric pumps, is to disconnect the input pipe to the filter, it just clips out - catch it in a jam jar.