Won’t start if parked on a slope

Hi,
Whenever I park my 2003 Defender TD5 115k on a slope it won’t turn over. I have to prime the fuel pump and crank it to get it to start.

I have replaced the fuel pump and the back wiring loom. But still get the same problem.

(On a side point, it does seem to be running rich ever since I had it chipped - where it just chucked out a load of black smoke, so I got them to just put the old TD5 spec back on the ECU. And it’s run a little rich ever since.)

Any ideas?

Does the engine turn over on the key?

lynall said:

Does the engine turn over on the key?

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Yes - turns over fine when parked on the flat. But any kind of slope, I have to pump the accelerator 5 times to prime the fuel pump and then pedal to the floor for 10 seconds until it eventually turns over

tedrino said:

Yes - turns over fine when parked on the flat. But any kind of slope, I have to pump the accelerator 5 times to prime the fuel pump and then pedal to the floor for 10 seconds until it eventually turns over

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Have you checked the leak-back pipes ...

no - good thinking - will change them and report back

Dippypud said:

Have you checked the leak-back pipes ...

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Not on a td5.

tedrino said:

Yes - turns over fine when parked on the flat. But any kind of slope, I have to pump the accelerator 5 times to prime the fuel pump and then pedal to the floor for 10 seconds until it eventually turns over

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Right so it turns over on the starter motor, but will not fire?
Was it like this before the tuner got his hands on it?

lynall said:

Right so it turns over on the starter motor, but will not fire?
Was it like this before the tuner got his hands on it?

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Yes it turns over and fires fine on the flat but on a slope it turns, nearly fires (sometimes does) then stops. As if the fuel source has gone. I then have to prime it and wait at 10 secs with pedal on floor waiting for it to fire before it eventually does.

No it never did this before I got it chipped and then reset but that was a long while back

tedrino said:

Yes it turns over and fires fine on the flat but on a slope it turns, nearly fires (sometimes does) then stops. As if the fuel source has gone. I then have to prime it and wait at 10 secs with pedal on floor waiting for it to fire before it eventually does.

No it never did this before I got it chipped and then reset but that was a long while back

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Right now I understand.
Have you popped the ecu plugs off and checked for oil?
Can you hear the in tank pump running? is the pump very noisy ie fuel starved?

lynall said:

Right now I understand.
Have you popped the ecu plugs off and checked for oil?
Can you hear the in tank pump running? is the pump very noisy ie fuel starved?

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No will check the plugs - yes the fuel pump is noisy.

tedrino said:

No will check the plugs - yes the fuel pump is noisy.

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I have had (on a disco td5) the in tank pump mesh filters block cause starting and running issues, the whole pump unit comes out and the filters clip off for cleaning etc.
Take pic of the pipe colours to pump so you do not mix up on refitting.

lynall said:

Not on a td5.

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Ah, the noo fangled stuff stumps everytime ...

I had starting issues after changing the fuel pump. I started checking things and there was no non return valve on the filter housing. Fitted in one and the issues went away.

Thanks - will check that

tedrino said:

Thanks - will check that

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One like this. Mine was missing for some reason

Dippypud said:

Ah, the noo fangled stuff stumps everytime ...

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Showing your age there