2004 boxer hdi fuel supply issue

[jgra1]

hi all.. decided to take the boxer 2.2 away for it's 3rd journey late yesterday.. starting with a 170 mile run to Taunton.
2 minor things early on..

after a roundabout, the fuel gauge went instantly from above 1/2 down to 1/4 of a tank and took about 1 hour to regain itself..not something the van has done before..
the horn wasn't working.

there was only 1 traffic jam, at Stonehenge, and shortly after, the fuel gauge (which by this point was just about 1/3 rd full, suddenly went to empty and the yellow fuel light was flashing.. then the EM light glowed on, the van stuttered, and we limped to the next roundabout, where she stalled.. I removed key, waited, and restarted..
fuel gauge came back to normal, EM light went off

she then carried on another 60 miles with no issues until a traffic light in Taunton.. EM light on and she sounded a little rougher.. limped 2 miles to mums and left her..

this morning I found anyone that would try and run a diagnostic (I had for some reason left lexia/PP at home!) and a local place around corner said yes, £30.. no problem I thought.. I started van up, EM light went out, got 1/4 of a mile and light back on..limped to garage and van wouldn't restart.

they couldn't read codes, citing an issue with my ECU communication.. and left me to myself really.. it wasn't the worst place to be, so i got some tools out, and removed the tank sender unit.
the short story is the pump is working fine, but there is no feed to it.. or rather the 12V + feed is only on for a few seconds, the fuel gauge flashes empty and the 12V disappears .. I cant speak for the Neg line there.. even for a few seconds the pump is now inaudible .

so, to get her back to mums I hard-wired the lift pump (from the leisure battery!) and van drove fine! and the gauge behaved too..

confused...

The main engine ECU is a contender I guess?
can i continue holiday by switching the lift pump on and off manually, or will something else now go awry. (I will probably take this route as a possible holiday or a tow truck home is a no brainer really)

I just did a BSI reset and no difference..
I also bought some contact cleaner in Taunton but haven't used it yet

any thoughts appreciated, especially concerning the power to the gauge sender and it's relationship to the LP lift pump,
and on my chances of getting around Exmoor and back to Kent with a hard wired LP pump

[lexi]

Is the pump fed by fuse or relay John. It could intermittent there if it is.

[electronmirror]

I don't know the Boxer HDI setup but if it's anything like the Xantia HDI the lift pump will only run for about 3-5 seconds if the engine doesn't start. This is safety related 'cos you don't want the lift pump continuously running and spraying fuel all over the place in the event of an accident and the engine has stopped.

I can't remember offhand if the pump is relay fed, probably is because it draws 5A. There are 4 wires, 2 thick and 2 thin going to the lift pump. The 2 thin ones are for the fuel gauge and don't affect the running of the pump. The other two thick ones feed the pump.

If the pump is completely inaudible then it's not running, check in the fuel filter bowl for signs of very fine brass filings indicative of pump failure. If that is the case a new pump is required and a thorough clean of the filter housing. If that brass swarf enters the high pressure pump severe wallet damage will ensue ! If there is no indication in the filter bowl then there may be insufficient pressure from the HP fuel pump to allow an engine start ( minimum pressure 200 bar), a faulty pressure sensor on the common rail or the beginnings of pump failure may be the cause.

[jgra1]

thanks lexi and ted..

yes i think there will be a relay and a fuse somewhere.. will have a look this morning.\Ted, the pump has always ran for a few seconds to pressurise ..you can hear it.. but now that doesn't happen.. the pump itself runs fine if i power the pins to it.. so I think the feed to it is the problem.. I suppose the 4 wires do share the same path from the tank up the bulkhead somewhere.. I will have a poke about as best I can today, and then if no luck will run a better ign live to the pump, and fit a switch so I have a bit of control over it ..

there is some correlation to the feed to the pump, and the gauge dropping off.. the gauge (now) drops down a few seconds after the ignition is switched on, and at exactly the same time - the measured feed to the pump stops.. all of this makes me think the problem is ECU related somehow...

the problem on the way down here was marked by the gauge flashing empty at me, and the engine light coming on.. the gauge is related somehow I am sure ...

[jgra1]

reading about ducato problems.. it seems a common issue.. there is a black (or white box) somewhere under the dash, with a 6 way plug.. this box may have A653 on.. this seems to be between sender float and gauge.. if its failing the gauge will misread or drop off completely ...

I wonder, if the ECU or BSI then thinks there is no fuel, due to this box, it will cut the fuel pump in the tank to stop it running dry? this could be an explanation?

[lexi]

Sounds plausible. Hopefully you can complete your trip and then get back to your tools and garage for a session of testing and fixing. Will be good to get that one sorted.

[jgra1]

thanks all and especially the two members offering diagnostic help.. van is fine. have ran a live from my fridge relay! pump always on and no issues .. going to leAve exmoor in a bit.. amazingly twice the van did countesbury hill in third ! fully loaded

[Stickyfinger]

Glad the + supply worked, did you put it on a switch ?

[Paul-R]

This sounds very similar to what I had to do with our old Xsara. After letting us down several times (the last being in France - by the time the breakdown van turned up it started on the key of course) I got fed up with it and wired in a fused relay fed from an ignition controlled supply. Result: perfect pump delivery and it was still like that when we sold it eight or nine years later.

[jgra1]

Paul sounds exactly like that!
thanks all for help, Sticky, yes I already have a switch on dash for activating the fridge relay.. (I could now move that switch somewhere less obvious if I am following your thinking)

The van made the rest of the trip fine.. I didn't get it weighed but may do this week..it is starting to feel heavy now.. 700 miles, half of them around Devon with all of the hills and torture.. about 100L of fuel, and I make that an average of over 30mpg! quite a lot more than I was expecting, all with stuff on the roof as well! yes it's a noisy slow drive, never daring to push over 60.. but that economy isn't bad at all.. the little 2.2 does feel well worked but has no complaints.. I still have no tow bar, roof awning, cycle rack or possibly a trailer with a bike on the back.. everything all increases weight really..

good trip though, Kent, Taunton, Wimbleball reservoir, the usual visit to Cloud Farm near Lynmouth, River Dart country park, then Bigbury, Brixham and back to Taunton/Kent

J