Disco Cutting out

I've been having an intermittant problem with my 1996 Disco TDi 2.5 over the last couple of years. It will cut out while driving as if someone has switched off the fuel (everything is working and the engine will turn over but will not start), I changed the fuel cutoff switch and have bleed the fuel system, but no joy, it could be hot, it could be cold, it could happen twice in the same day, it could be months between cutouts. If I just leave the vehicle standing for 5 or 10 mins it'll start up no problem, priming the lift pump sometimes helps but not sure if this is helping or it's just that it been standing long enough. Anyone got any ideas before I go through the expence of starting to replace the fuel system

Hi it could be a blockage in your pipes have you ever cleaned out the filter bowl underneath,if you can hand prime the fuel filter then the lift pump should be ok,have you checked the voltage at the fuel cut off switch when cutout not an immobilser fault is it also last thing check that the fuel cap is not causing a vacuum took me 2 days to find this fault on a car with similar faults try the easy ones first good luck tiga.

I cleaned out the sediment bowl at the rear and changed the fuel filter then bleed the whole sytem through but it still happened, I thought about the vacume so checked the fuel cap when it had stopped but seemed ok (no sucking noise when I opened it). Someone mentioned that there is another fuel pump in the fuel tank and if it doesn't work the pressure is not maintained????? Don't suspect an immobiliser fault as the engine turns over fine just will not start.

Dont be lured by the dark side my friend,just because it cranks dose"nt mean its not immobilised my car has a toad immobilsor fitted as well as standard LR system but every now and again my car will not crank but i can roll it down hill and it will start so why wont it crank,defenders also suffer from 1 circuit working only so do v8s but v8s is always the power feed to the coil it looses,it dont take 2 minutes to check for a voltage or just connect a 12v feed directly so you can rule this out,also the diesel does not have a fuel pump in the back its a sender gauge only but is identical looking to the v8s,you have checked most other things so not sure what other advise i can give but i will have a think,is it manual or auto,cheers tiga

thanks tiga, The next time it cuts out I'll stick an avo between the fuel cutoff and the feed understand that as long as the ignition is on then I should get a reading. If this is okay is there anyway I can check the immob or is this a workshop job? Just though last year the whole thing wouldn't crank and I bumped it okay so immob is looking suspect. If I don't get a reading on the fuel cutoff does that point to any particular unit?

Hi again if you get no feed i would say the immobilser is going wrong as they all have common faults,the alarm spider is located behind the dash so in my opinion its only about 25 mins to remove dash well thats me but i have done a few,i would leave the standard alarm system alone and would fit an after market immobilser,i know you can get a link lead from landrover for defenders to by pass the circuit,this just plugs straight into the connector you take out of the spider,would have to check if this is same for disco as its still enables you to use central locking and alarm,i have taken the spiders apart and its only normally a couple of dry joints inside,but taken dash out once is ok more than once is a pain,i will have a look on my rave discs regarding wiring,but normally the spider just creates an earth path for starter and fuel,will have a look after children go to bed,cheers tiga

Thanks tiga, looks like I've got a dash to take out, not the best time of year to be doing it.

Hi from that reply i take it that its loosing its 12v feed then,you could always just wire it up to a 12v ignition feed for now and worry about it again in the summer,tiga

It hasn't happened for a while then it started again in the cold weather it didn't loose the 12v feed after some more testing (as it is cutting out more frequently) I put an avo over the feed and got a reading then got someone to turn it over and the feed stays constant putting the feed back on live you can hear the fuel cutoff operating but no start. So I have power turning the engine over and everything electrical seems to work I have a fuel supply but it's not starting it can be left to stand for a while and it'll start, I've bleed the system at the fuel filter and at the overflow return pipe on the pump, hate to ask but could it be the injector pump?

hi there, hope you dont mind me jumping on to your thread but i have the same problem of cutting out on my N reg 2.5tdi. Intermittent cutting out and wait 10mins starts fine, my central locking is erratic and sometimes works sometimes doesnt - does that point to immobiliser? I had it serviced and ran fine for 6 weeks now started again- made me think it was fuel system- the garage have not had much joy as it always seems to work when they get it.
If it is immobiliser can i just have it deactivated as i am not too bothered about it being nicked?
cheers Bob

Don't mind at all as long as we can get to the bottom of this. After a lot of thought I'm putting it down to a combination of two things firstly the fuel pump in the fuel tank not presurising the system and secondly what is causing it to cut out air getting in to the system when this starts happening I can bleed some air from the fuel filter and the system shouldn't have any air at all, so I'm going to fully bleed the system as per the book and see how long it takes before the problem comes back, I'm also going to lift the sender/fuel pump out of the tank and see if it is pumping fuel when powered up. If that doesn't cure it then I've got to have the dash out to change some bulbs so I'll have a look at the spider then.

ChrisK said:

It hasn't happened for a while then it started again in the cold weather it didn't loose the 12v feed after some more testing (as it is cutting out more frequently) I put an avo over the feed and got a reading then got someone to turn it over and the feed stays constant putting the feed back on live you can hear the fuel cutoff operating but no start. So I have power turning the engine over and everything electrical seems to work I have a fuel supply but it's not starting it can be left to stand for a while and it'll start, I've bleed the system at the fuel filter and at the overflow return pipe on the pump, hate to ask but could it be the injector pump?

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Hi! I have the same problem with less money to fix as you had - can you tell me what was the problem in the end? Could you solve it - I know this is almost 2 years ago - I am desperate!
Mine is a disco 1(1997)
Werner Van der Merwe

It was the Spider that works with the engine cut off for the imob I got a terminator for about a fiver which replaces the spider but the imob doen't work the way to test is to put a live feed to the fual cutoff sender and your problem will go away, you have to stall or disconnect the live feed to stop the engine.

Oh, I found a document on the internet somewhere that tells you how to do the change as it behind the radio.

Hello
I have had excatly the same problem on the same age disc. It would cut out then wait about 2 mins and it would start again OK. I have replaced the lift pump this weekend and so far OK. But it has run before ok for 200 miles but in the last week before changing the lift pump it cut out 3 times in 10 miles. Time will tell