300 Tdi Fuelling problem. Help....

Hi,

I've got what appears to be a fuel starvation problem with my Disco and I'm hoping you guys can provide some help in pinpointing the problem please.

It's a 1998 300 tdi auto. It's done 80,000 miles. EDC throttle. Runs on a mix of veggie oil and diesel, nothing too extreme though.

On Monday it was running fine until I put my foot down on the dual carriageway. It then lost power, wouldn't rev and finally cut out.
Got it started again and it was fine for about 50 yards and then lost power again.
I managed to limp the car home and it wouldn't idle properly, started to hunt and then cut out. Took a long time on the key to start as well.

I changed the fuel filter and tried to bleed the thing but it wouldn't have any of it. The lift pump was really naff even when I got it on the cam.

The fuel pump was changed yesterday and seemed to solve the problem. Car was driving better than I can remember.
Then I got out of the 30/40mph limit and power/revs dropped off again.
Lift pump was definitely f*cked, but what now?

I topped the car off with another 30 litres of diesel, in case there was a fuel problem, and tried again. Problem still there.
I can't get it to rev above about 2700 rpm. No smoke, no violent juddering, no oil in water.

I cut the old fuel filter open and it was clean, no jelly, no crap.

What next ? Has a load of crap been sucked up from the tank ?
Blocked fuel pipe ? Is there a gauze filter in the tank that could be blocked ?

Cheers for any help.

have yu got a sedimenter over o/s rear axle? if so try checking that - but :search: on here first to save yoself heartache

Yes, cheers for this. There is a sedimenter above the axle. I cleaned it out a few months ago but it wasn't bad then. Not looked this time, yet.
I had a very similar problem whilst driving around Devon but it "self cleared" the same day, so I was none the wiser at the time as to the cause.
I'd read the threads about veggie mix sucking crap out of the tank so I thought the sedimenter would be full of it.

The car is back in the garage so I'm waiting to hear if they've found anything, if not I'm going to be stuck until the week-end before I can start looking.

Did you change the seal when you cleaned the sedimenter? If not, it could be sucking air and not running properly. Even if you fitted a new seal, you need to make sure that the bolt is tightened securely to prevent air ingress. Also, did you clean it out thoroughly? As there is a possibility that some rubbish may have become dislodged, partially blocking a fuel line, or contaminating the diesel filter.

Just out of curiosity, what state was yours in when you removed it? I had an inch and a half of sand/sludge in the bottom!

HTH,
Lew

I have just had the same problem, it was fixed by changing the fuel filter. the filter had a jelly substance in it and had only been replaced 3 weeks before. I cleaned my sedimenter and found it full of water and sludge. I am currently running on 50/50 veg/biodiesel. not done meny miles since the new filter was fitted so don't know if it was the water mixing with the veg or not at the moment but i hope that has sorted it. the filter that clogged was a brit part filter and i have replaced it with an better one ( can't remember which)

DiscoLew said:

Did you change the seal when you cleaned the sedimenter? If not, it could be sucking air and not running properly. Even if you fitted a new seal, you need to make sure that the bolt is tightened securely to prevent air ingress. Also, did you clean it out thoroughly? As there is a possibility that some rubbish may have become dislodged, partially blocking a fuel line, or contaminating the diesel filter.

Just out of curiosity, what state was yours in when you removed it? I had an inch and a half of sand/sludge in the bottom!

HTH,
Lew

Click to expand...

Lew, thanks for the response and the suggestions.
No, I didn't change the seal but I was careful about tightening the thing back up and holding it square to the seal.
I did clean it out properly but this was about 3 months ago, just after it had exhibited a similar problem.

After reading the posts here, I fully expected it to be full of crap / jelly / sand / lard etc.
I was most disappointed to find almost nothing, just a few slimey bits at the bottom !!

I haven't touched it since, and it had been running fine.

I've got a new seal for the thing so I'll check and replace this time.

hifly said:

I have just had the same problem, it was fixed by changing the fuel filter. the filter had a jelly substance in it and had only been replaced 3 weeks before. I cleaned my sedimenter and found it full of water and sludge. I am currently running on 50/50 veg/biodiesel. not done meny miles since the new filter was fitted so don't know if it was the water mixing with the veg or not at the moment but i hope that has sorted it. the filter that clogged was a brit part filter and i have replaced it with an better one ( can't remember which)

Click to expand...

Hifly, thanks for the response and the information.
I think this is the first time I've actually seen someone say that they've had the same problem and fixed it !!
I think I had two problems, first was the knackered lift pump, and second is probably air or crap being drawn in under load.
I changed the fuel filter and cut the old one open. Mine was also a Britpart item, the new one is EFI i think.
Any way the old one was clean, no crap in it at all. I'd have been happier if I had found some.

I'm not running any more than 40/60 veg/diesel mix, probably less veg most of the time.
I'm definitely not using the KTC veg oil as I tried that and saw what it went like when I stored it in the garage during the winter.

I think everyone is pointing me towards the sedimenter or pipes being at fault.
Thanks for this guys, as I was a bit worried it was going to be on the expensive side of the fuel filter...........

if you want to check if its air getting in put a piece of clear pipe between the filter and the injection pump, you will see bubbles if air is getting in. also as the weather cools the veg gets thicker and you have more chance of a week joint letting in air. Adding 5% petrol will help to thin it. The best veg oil for winter is sunflower as i think its cloud point is about -10.

not sure if you are on the veg/bio forum but if not here is a link

vegetableoildiesel.co.uk - Powered by XMB

its nearly as good as Landyzone

hifly said:

if you want to check if its air getting in put a piece of clear pipe between the filter and the injection pump, you will see bubbles if air is getting in. also as the weather cools the veg gets thicker and you have more chance of a week joint letting in air. Adding 5% petrol will help to thin it. The best veg oil for winter is sunflower as i think its cloud point is about -10.

not sure if you are on the veg/bio forum but if not here is a link

vegetableoildiesel.co.uk - Powered by XMB

its nearly as good as Landyzone

Click to expand...

Hifly, once again thanks for the tips. really useful.

I was thinking of putting one of those clear, in-line, fuel filters in so that I could see if anything odd was happening.

I'll check out the veg forum on the dark side.

I'm currently running sunflower oil as I really don't trust the cheapy soya stuff.

Info' if anyone is interested is, Tesco's Cereo Sunflower, currently on special offer (not as good as the one a couple of months ago though).
It comes in 10 litre and 5 litre plastic bottles with a carry handle.
Price is £8 for 10 litres and £4 for 5 litres.

Tesco's cheapy soya oil is about 62p /l at the moment.

Here is an extract from an article on 'Biodiesel';

''Here is an extract from an article on 'Biodiesel';''

Who wrote this, where was it published...?

You cannot make a judgement based on one article...there is plenty of evidence to the contrary..especially when dealing with a land rover engine such as a 2.5N/A or 200tdi...these are durable, well tested engines that can run on SVO or WVO..

True biodiesel is entirely F.A.M.E.-fatty acid methyl esters-this can be made from any vegetable or animal oil-during processing of the original oil into FAME(transesterification)the glycerine backbone of the original oil is removed.The resultant fuel is much thinner than the parent oil,almost the same viscosity as derv.
You may only be able to buy 5% biodiesel at the pumps,but diesel engines run quite happily at any ratio right up to 100% biodiesel(mine runs on 100%).
There are reported problems (irritations,rather than true problems)associated with running vegetable oils-ring gumming and excess carbon deposits(mainly blamed on the low combustibility of glycerine present in the oil)but these only tend to appear after extended use over many thousands of miles,water injection is considered a good cheap antidote-some are reporting good success.
I have never heard of anyone destroying an engine by running on vegetable oil,on the contrary bio fuels normally extend engine life by there slower burn characteristic and better lubricating properties(this is why diesel engines run quieter on bio fuel and cleaner as a bonus)

as always its the half truths that get all the press, cold veg oil will kill a lucas pump, it won't do a common rail system any good either,

a bosch pump, as fitting in the disco is 100% ok with veg oil, the only slight problem with the disco is its a direct injection engine which can suffer from ring gumming due to cold oil hitting a cold piston when first started, this can be over come buy a good oil chage regime, i flush at every oil change (5k miles) with 50/50 diesel/clean oil run for 20 min's, then new filter and clean oil.

My direct injection transit has done 50k miles on veg 200k miles on clock and is running as sweet as a nut. Some guys on the veg forum are trying water injection (when hot) and have reported good results at fixing ring gumming.

Most people get it wrong because they don't do the research and just chuck it in the tank, with a disco 200/300 it will be fine, with newer/other cars you can do £000's of damage.

Well it's fixed, fingers crossed !!

Thanks for all the suggestions.

The fuel filter was clean, no crap.
The sedimenter was clean, no crap.
No air leaks found in pipes, no rusty fuel pipes on top of tank.

We did find some muck in the pick-up pipe from the tank to the sedimenter though. So, Fuel lines and tank cleaned out.
Also changed the fuel filler cap. Didn't seem to vent properly.


Anyway, it will now once again rev over 2700 without cutting out.
Along with the fuel pump change it now pulls really well, and just seems like a different beast. . Much less throttle pedal needed for anything.

It's amazing how you just fail to realise how bad a lift pump is as it starts to fail over a period of time.

Definitely recommend anyone with a 75,000 mile disco to change their pump if you think the sparkling diesel performance has dropped off.