Thread: 98 disco 300 TDI Auto Power Loss

Apart from the things you can check ( ie clean the intercooler & pipes, air cleaner, sedimenter, fuel filter and earth straps, and the HP air line from the turbo to the fuel injector pump) and the chance you've picked up a questionable load of fuel ( a big dose of diesel injector cleaner will help if it is so) it may be you're timing is off a little - When was the last time you looked at that area?

Thanks for the reply,

The timing seems ok, just a little down from what I would think as normal. last night when I drove home I took down the motorway and it went as fast as i wanted ( engine was warm ) but this morning and lunch time it would not budge above 80 and the rev needle would not move any higher.

I am drawn perhaps to a turbo hose or diaghpram, as purely a guess, although it revs and accelerates freely and fast until last gear kicks in and then thats all she wrote.

My commute is about 4K each way so I have it booked in at Ricks 4WD on the Goldcoast end of next week. So long as it does not get worse I can get by for now, but any assistance still welcomed


Thanks for your help

When you checkout the filters don't forget the one near the fuel tank.
I take it you have checked the air and main fuel filters?
Also make sure you have Diesel in the tank and not petrol. My dad managed to do this and very luckily didn't do any damage. Engine would idle and run but didn't have alot of power and run alittle rough and higher revs. Noticed it when we checked the fuel filter and it smelled stronger than normal diesel.
Wasn't easy draining the tank either.

Does it rev above 3000rpm in any gear??

Sounds to me like the lift pump is stuffed, the injector pump will suck the fuel up as long as there is fuel in the lines, but if air gets in you will never get it going. leaving it over night the fuel seeps back slightly and hence your 2nd time start. Had this happen before in a mates disco. wouldn't rev over 300rpm as it ran out of fuel delivered to the injector pump.

I would reckon the fuel filter. That's why you need a spare in the glovebox. 10 minutes to changeover.

So I was doing 110kmh down the motorway….. when gradually, as if I was lifting off the accelerator the speed dropped down to about 85 and the revs declined from 2400 to approx 2200 and levelled off. I kept my foot accelerator position the same and after about 15 seconds speed and revs gradually climbed back to the original readings. This happened several times over a 10k stretch doing 110kmh. The only over thing of note was that when turning off the motorway slip road and lifting off the accelerator, just before the car came to rest the revs counter suddenly dropped from about 8oo to 400 like a stone and the engine sounded like it might stall. As soon as it dropped though the rev counter would fly back up to about 800 and behave normally.

Gentlemen, if anyone… ANYONE has any words of wisdom that might explain the strange goings on with my 300 TDI Discovery I would be very grateful.

Thanks

Gozzie

It appears that I do infact have deisel but I am dubious of it's quality,

I have cleaned the air filter and checked the hoses and appear normal.

I have drained some fuel from the filter by the brake servo by unscrewing the plastic nut and allowing some to run free, I believe this is meant to release any sediment etc.

On the rear filter near the fuel tank I was able to remove the plastic screw ok, (I believe this is the one that breaks easily). Let some fuel escape and then replaced the plastic srew again. I would have preferred to remove the whole untit and clean it but as I was working by touch, does the unit have a nut holding it on or is it a question of unscrewing by hand. From the filth surrounding it I do not think it has seen much attention for a very long time. Any tips in getting it off as I do not want to force it.

Also I am not getting over 3000 revs in any gear.

Thanks

Gozzie

definitely a fuel delivery problem.

When i fitted my new engine over the holidays i mixed the banjo bolts up on the ijnector pump, one has a big hole in it and other has a small hole in it. After a helpful AULRO member suggested this i swapped them and problem solved. So somewhere along the line something is affecting fuel flow, but only intermitently for some reason.