I've read across various posts relating to the TD6 in tank fuel pump.

Bit of background: - car was purchased as non runner, inline fuel pump, diesel filter and fuel pressure switch made the car a runner again...yay !. But when the tank would get to less than 1/4 a tank the vehicle would cut out. I have been treating 1/4 a tank as empty since then for a few months now and living with it.

During the initial diagnosis of mine, I have had the entire fuel system tested at a fuel injection specialist, leak off test, all fuel pressures monitoring during a drive as I don't have that equipment myself.
I know the high pressure fuel pump has been changed in the past (however I can't confirm the condition of it of course, looks newer than the rest of the bits on the vehicle)

Now ...........it's getting worse, as the vehicle would start to cut out at just over 1/4 a tank now.

See video -

So got myself a brand new in tank fuel pump & sender, as the kit came with the left hand fuel sender I swapped that out as well. There wasn't any accompaniments in the tank (we'll only a few small bits) but I drained and disposed of 15 litres of diesel
I haven't checked the wiki, but if there isn't a write up in there for how to replace this, i'll write one up with a few pictures.

Job took a few hours as I was faffing (including the drain). I re-added 10 litres of fresh diesel, 5 litres in the left hand tank as I had access, and 5 litres in the right side, via the filler cap.
The minute I re-attached the battery and turned the key to position 2 to let it prime, I got the "fuel injection system" error on the dash, without even starting the car. I checked for leaks around my work and there were none.

I started the car and it started with no issues, I rev'd the vehicle a bit and checked the connections for leaks again.

Took the car for a test drive and I still saw "fuel injection system" error, yet the car drove fine.
I did note that when I put my foot down, the message would go away I can only assume that fuel pressure had returned to normal, but then when I removed my foot from the accelerator the message would come back again but the car still drove fine, I put another 20 litres of diesel in it, fuel gauge crept up to 1/2 a tank.

Before I take the car back to the fuel injection specialist to perform some more checks, is there anything I might have forgotten to do during the re-fit ?

Here's whats happening now during normal drivin (error message displayed) and putting my foot down under hard acceleration the message goes away.



Thanks

You get the fuel injection system error warning from the sender ontop the fuel filter if you are not getting enough pressure around 3 bar, it should if healthy be closer to 4bar. If you are sure the tank pump is good I would be looking at the external one. There is a good video how-to on youtube for the in tank sender unit, it's on a V8 but I followed it to change just the pump in mine

https://www.youtube.com/watch?v=YMWxPwgeLBQ&feature=youtu.be 2007 TDV8 VSE
2003 TD6 gone.
2002 P38a gone
1999 P38a gone
1997 p38a gone
1993 VSE gone
1992 VSE gone
1966 Series 2a with V8 conversion gone

Hey

Thanks for the reply, as noted in the initial thread.Ive just changed this as it was faulty. The new one uses a bosch motor so i know its a quality part.
The old one is currently waiting to go the tidy tip.

The pressure sensor on top the diesel filter, i changed that a few months ago with a britpart one so it should be reading correctly (was getting air bubbles in the clear pipe)

I have however noticed that the feeder pipe to the high pressure pump has started leaking since this morning, wasnt doing that yesterday.
Either way, I cut off the rubber bits off the pipe and re attached on bith sides of the high pressure pump.
Its no longer leaking (i think now the in tank pump is sending higher pressure it must now have been leaking past the weaker part of the pipe)

Started the car and it went away for a few minutes, but then came back again

The low-pressure pipes to the high-pressure pump are a common leak point and as you have done a quick fix. There is always a chance of a faulty new pump however I would be checking the pump relay in the back fusebox and the relay in the ECU box at the front. Also the wiring/plug on the external pump. The pump in the Tank is a lift pump the external pump provides the 4bar pressure to the high-pressure pump. When my Tank pump started to fail, when I floored the car at speed it just bogged down as if it was running out of fuel, otherwise drove fine with no warnings. 2007 TDV8 VSE
2003 TD6 gone.
2002 P38a gone
1999 P38a gone
1997 p38a gone
1993 VSE gone
1992 VSE gone
1966 Series 2a with V8 conversion gone

Following this thread as I've had similar issues in the past and thinking about replacing in-tank pump. Now with working from home, I've got plenty of time to mess around with the car. 09 RR Westminster 3.6TDV8 - Stornoway Grey / Black interior - now gone (sad face)
Nissan X Trail 1.6TDCi Tekna
Fiat 500 1.2

wayneg wrote:

The low-pressure pipes to the high-pressure pump are a common leak point and as you have done a quick fix. There is always a chance of a faulty new pump however I would be checking the pump relay in the back fusebox and the relay in the ECU box at the front. Also the wiring/plug on the external pump. The pump in the Tank is a lift pump the external pump provides the 4bar pressure to the high-pressure pump. When my Tank pump started to fail, when I floored the car at speed it just bogged down as if it was running out of fuel, otherwise drove fine with no warnings.

wayneg wrote:

The low-pressure pipes to the high-pressure pump are a common leak point and as you have done a quick fix. There is always a chance of a faulty new pump however I would be checking the pump relay in the back fusebox and the relay in the ECU box at the front. Also the wiring/plug on the external pump. The pump in the Tank is a lift pump the external pump provides the 4bar pressure to the high-pressure pump. When my Tank pump started to fail, when I floored the car at speed it just bogged down as if it was running out of fuel, otherwise drove fine with no warnings.

You know that reminds me, i had a 1300 cdti corsa mant years ago.
It would start fine with easy start but not start on its own. The o ring failed exactly as you show there.

It didnt start on its own as it couldnt build up enough pressure in the fuel rail, so it was sending all of it down the return

Yup. Same as this one. Easy start down it’s chuff would just give it enough to start. Ran like a bag of spanners with now power tho. But that could of been the fact 3 injectors where shot and both pumps tired too
Worth a look it’s only an hour so to strip it off. I got a replacement from an X5 at a scrap yard

Yea, guess it would be worth a look.....but then as I said, runs, drives fine far as I can see.
Have I got yo remove the high pressure fuel pump to get to it ?

On my corsa it was at the end of the fuel rail but looking on line it looks like its on the side of the high pressure pump ?

I reacon ive now done 120 miles in this thing and it hasnt skipped a beat, all i see
is this stupid message !!

Ill let you guys know then in that case

It’s on the back of the HP pump but accessible without removing said pump. I think I took of the inlet manifold an injector pipes. I did have to use every extension I own and a lot of sweat words. But it is possible.
If you still getting a message then I’m guessing it still thinks there is still a fault. On mine the injector message went away once I cured it.
A good snap on reader will pull some codes an read the live values you need for fueling. Maybe easy to get hold of one of them locally

Before I remove the fuel pressure reg on the side of the HPFP, I took the car to my guys down the road to plug it in, as my code readers didn't find anything, one of them only found the engine ECU and displayed no faults so I just chucked it back in the drawer, so I got them to plug it into their solus for me

Its come up with the following codes along with the message on the dash

P1260 - Delivery Fuel pressure monitoring
P1255 - Delivery fuel pressure sensor

So despite me changing the lift pump and external in line pump for (good measure) with bosch parts its still winging about fuel pressure.

Bear in mind I only changed the lift pump as it was cutting out at 1/4 tank and after having the entire car looked at a few months ago at a fuel injection specialist who advised i've probably got a dodgy tank pump (which I did)

I mean if the engine starts & drives fine and I can now run the car to the fuel light coming on (where i couldn't before) the only thing i can think of is : -

-I might have fouled one of the syphon tubes on the left side of the tank (i'll check that now, but i'm not hearing any additional wining noises coming from the pump just normal operation)
-i've got the wrong in line fuel pump <bosch> but the car was winging before that, so who knows it may have hag the wrong in line fuel pump all along
-Or one of these pressure sensors has failed (the one on the top of the fuel filter has already been changed) or it could be the rail pressure sensor

Struth !

Live values of the pressure will help too. Think they want 3.5 to 4 bar at tickover. It was a solus I used to see that data which showed low pressure as it cranked. Once it got running the HP delivered plenty for it to run well by shear force. But cranking it where it showed up on live data.

Youre right, im into the wind otherwise.
My code readers found nothing, hence why I drove it down the road. they dnt charge me anything for a quick read anyway but getting the pressures, id have to give em something ofcourse.

Ive decided im not convinced by the pressure reg at the side of the HPFP as the car starts n runs just fine so im gonne leave it for now.

I decided to double check my work and nothing is fouled or overtightened, i “carefully” took a vid of inside the tank on airplane mode, if it was petrol I never would have attempted this.
The pump hums and you can see the return feed tricke up the pump.



Just before the fuel filter, if only i had a guage lol. But it fills this 2 litre coke bottle in next
to no time, so im also convinced its working to spec.



Off to get the pressures read then ..........