Disco 300tdi won't start

Hi guys, help required please. My '94' 300tdi discovery died on me yesterday, whilst driving noticed a sudden loss of power going uphill, started running rough on the motorway with a duff injector feel, like it was firing on 3 or even 2 only, managed to pull off to a services area and yep on dipping the clutch a definate duff injector feel as the gearstick jumped around along with the engine. Parked it switched off and could not re start. Engine turns fine, no overheating, no loss of fluids, oil and water levels unchanged. Cracked the connections at the injectors open and there is some fuel getting to the injectors. On cranking the starter engine 'almost' fires running at about 400rpm for just a second off the starter with accelerator fully depressed (not as depressed as me tho). The non start does seem to be like fuel starvation. i wondered if the lift pump might not be delivering enough to the injector pump (no visible sign of any leaks either) but not sure if there are any other electrical possibilities?
Thoughts anyone.

oh welcome to the forum:clap2:


an i haven't gorra clue:laugh:








but it does sound fuel related

just a suggestion, could it need a new fuel filter

It could be the fuel solenoid is sticking and not opening, or there is a bad connection to it and its not holding it open properly. Check that, also check that there is 12V coming along the little connector, if not, get a wire from the battery to it and try starting it. If it works then its the immobiliser which does sometimes cause this type of fault but usually with the starter feed.

I would loosen the bleed screw off or take the fuel filter off, and pump the lift pump does diesel come out? If not blimp engine on the starter to get the pump off cam (it only pumps manaully off cam).

If you get NO diesel from it then its probably your lift pump (you can always take the filter off and get someone to turn it over - if it sends diesel everywhere its fine).

If you rule that out, change the filter and give that a go.

If at this stage you still don't have it going - yet you have a good flow of diesel to the injection pump then its possibly going to be the injection pump at fault. You say you had the injection line unions off, do you see a reasonable squirt of diesel from each?

I just slackened the connecting nut at each injector in turn and cranked her over, there was diesel coming through.

The question now is, is it coming through with enough pressure and are the injectors OK.

I would still put a new filter in. It may still be fuel starvation related. The IP will suck enough to get the diesel from the tank if the lift pump fails.

So I would still be checking this pump.

scotsigns said:

noticed a sudden loss of power going uphill, started running rough on the motorway with a duff injector feel, like it was firing on 3 or even 2 only
Cracked the connections at the injectors open and there is some fuel getting to the injectors. On cranking the starter engine 'almost' fires running at about 400rpm for just a second off the starter with accelerator fully depressed

Click to expand...

I'd have a look at the turbo/intercooler hoses, they can collapse internally and cause similar symptoms.

Not non starting - unless it collapsed and sealed up like this.

That's exactly what happened to a mates ... tube collapsed in a spiral, de-laminated rubber, which all balled up and was sucked into a 'blob' which effectively cut the air supply off.

Worth checking anyhow, IMHO, two minute job to get the pipes off and have a look, if only to prove it's not a problem. Or just disconect from the turbo and try to start.

Have you still got a timing belt?

Andy.

If he has diesel at the injectors then yes he still has a timing belt.

take the sound deadening cover off the top and see if your rocker cover bolts are loose! mine did exacly the same turned out to be the rocker shaft had snaped!

My 97R 300Tdi auto lost all power whilst driving at 50mph on a level main road, would start and run, ticking over fine but no power to move forwards (or backwards). I was alone and it was dark so called the RAC, roadside patrol insisted it was a fuel pump problem and it had to be recovered, turned out the intercooler hose collapsed, luckily a cheap fix.

thanks for all the ideas guys, final diagnosis is the injector pump! its getting fuel up there but no pressure behind it unfortunately. OUCH!