td5 dies with more than 1/3 throttle

[josh aka sean]

Hi all
I have just purchased a 2000 discovery td5. As the title suggest its runs fine until more than 1/3 throttle is given and then dies. I am assuming it is a fuel delivery problem at this stage but not sure where to start. Any suggestions would be good
Thanks
Josh

[Psimpson7]

Is that just when under load or all the time. I.e . does it cut out at no more than 1/3rd throttle in neutral.

Can you hear the fuel pump start when the ignition is turned on? You may have to put your head in the off side rear wheel arch when someone turns the ignition on.

When driving (if possible) if you dont use more than 1/3rd throttle will it rev through?

If so it may be the throttle pedal as opposed to a fuel pump.

[Catmatt]

Hi all
I have just purchased a 2000 discovery td5. As the title suggest its runs fine until more than 1/3 throttle is given and then dies. I am assuming it is a fuel delivery problem at this stage but not sure where to start. Any suggestions would be good
Thanks
Josh

Discos don't have a throttle cable between pedal and injection system as they have a 'fly-by'wire' system. The potentiometres (Spelling) and throttle position sensors sometime fail giving erratic throttle 'settings similar to what you describe.

I don't suspect it's a fuel pump issue - they either work of fail totally.

I agree with Psimpson7 - have a dealer do a diagnostic check. They'll tell you within 5 minutes if its throttle pedal.....or get hold of a Nanocom and fault find.

Cheers ;)

[Graeme]

Sometimes a TPS will develop a dead spot which can be pushed past if you're quick enough. I had one that had a dead spot just off idle which was "different" to drive in stop-start Canberra traffic using the all or nothing approach.

[Catmatt]

Sometimes a TPS will develop a dead spot which can be pushed past if you're quick enough. I had one that had a dead spot just off idle which was "different" to drive in stop-start Canberra traffic using the all or nothing approach.:D:D:D:D:D

Yes the traffic in our National Capitol of Public Servants can be........"challenging" :p

Particularly the Consulate plated vehicles that quite often forget that we drive on the LHS of the road!! It's a challenge to find a car driving around a round-a-bout the wrong way.....numerous times until they finally work it out ;);)

[eckolsim]

Check the sense line between the air intake and the turbo waste gate controller.
It's a small black rubber hose that runs from just behind the air filter box from a stub on the air intake assy. The turbo waste gate controller lives near the aircon pump.

If this line is removed or split you will see these issues. It can happen during servicing if the mechanic is not paying attention.

If you need more info then ask and I cam sure a photo will turn up.

Hope this helps.

[josh aka sean]

Sorry I haven't replied. Thanks for all the suggestions. I forgot to mention earlier that the vehicle is currently in Victoria at a relatives house (while i'm in cairns) so have to relay information to them to have a look at for me and then get back to me. At the moment I'm in the stages of waiting for them to get back to me. Thanks again for the suggestions.
Cheers
Josh

[josh aka sean]

Hi again
It appears that it is rev related. If held on brakes and full throttle is applied will hold low revs. I may have been miss leading with the statement that it dies (miss understanding over the phone) it apparently surges heavily. further to this did have the fuel filter light come on briefly for around 10 sec and has since gone off again. We are currently going to change the fuel filter but any other suggestions would be appreciated.
Sorry for the vague information i've provided so far.
Cheers
Josh

[d5disco]

sounds like the problem i had on a td5. the dealer fitted a turbo boost valve for $133 a year or so ago

[Graeme]

further to this did have the fuel filter light come on briefly for around 10 sec and has since gone off again. We are currently going to change the fuel filter
Drain some fuel from the fuel filter in case there is water although the water sensors have a habit of giving false alarms.

Sounds like oil in the harness at the engine ecu if revs are only low at full throttle without any load.

[josh aka sean]

Sounds like oil in the harness at the engine ecu if revs are only low at full throttle without any load.

Revs were low when it was in gear and held on the brakes at full throttle. It hits about 1/3 throttle then starts to surge badly.

Cheers
Josh

[Graeme]

Ah, so the problem is occuring under load. Excessive boost fault then, so likely to be the modulator as already mentioned but could be the wastegate actuator has failed or the wastegate is stuck open. I suspect the loss of engine power occurs around 2500 rpm which is when the turbo produces too much boost if not limited which triggers the ecm to cut fuel until boost is no longer excessive, hence the surging.

[dundee3012]

i have seen the fuel pump fail and the engine will still run but with limited power. the only reason it will run is because the injectors have enough scavange to suck fuel you may find that once you change the fuel filter the fuel pump will not prime as you have allowed air in the system and now the pump will not work. when you free rev the engine ie netural or park will it rev over 3000rpm?

[Graeme]

i have seen the fuel pump fail and the engine will still run but with limited power.I should have remembered that one. I had just fitted a pressure gauge to a friend's TD5 to check the fuel pressure because it was having much the same problem but found the engine wouldn't start anymore. I thought the pump must have finally died right then but perhaps the injectors lost their prime when the gauge was fitted in place of the fuel temp sensor. Anyway, a new pump was indeed required.

[josh aka sean]

Hi all
After some further investigation have found that the small rubber line that runs from the inter cooler inlet to the waste gate controller is missing. So am assuming that currently the waste gate is not working correctly which would give high pressures. Will replace this and see how it goes. Don't think that it fuel pump gone as it can get upto speed just can't get over 2500 rpm.
Thanks
Josh

[josh aka sean]

Hi
Turned out to be missing air line from inter cooler to waste gate controller $12 later no more surging
THanks
Josh

[eckolsim]

Woohoo! Picked it....

Unfortunately these experiences come from being there yourself.

Oh, I too discovered my fuel pump had died after changing my filter chasing a low power issue.

So, now all you need to watch out for is coolant leaks, head gaskets and prop shafts and you will catch up to the rest of us. :twisted:

Sorry, forgot oil pump bolts. :(

[alpick]

And tranny fluid cooler line swage fittings that let go 300 km east of Alice springs!!!!!!,

That screws your day!