Defender 2.2 tdci 2015 jerky throttle off road

[StuntCock]

Evening, this is my first visit to this part of the forum, hoping for advice on a new to me car issue.
I’ve had defenders as daily drivers for over 25 years, 200tdi, 300tdi, TD5, 2.4 puma and recently swapped to a 2015 defender 2.2 tdci 110. In the main I am pleased with it, but have one really annoying problem.
I live at the end of a long bumpy forestry track, which requires slow uphill driving. 2nd gear low revs type stuff. The throttle response on this car is really jumpy, so as you go over bumps the car surges and jerks like a bd. It is like riding a kangaroo!
I guessed maybe the throttle pot on the pedal was no good, so swapped it for another, but no difference.
A bit of googling suggests this isn’t a rare problem, some say drive in low box, others say it may be clutch switch issue, some say a remap is needed. Others say learn how to drive it!
I doubt by 2015 Landrover would not have sorted such an issue, so doubt it is driving style or remap?
Any pointers gratefully received! Thanks.

[100SRV]

What's the behaviour like when climbing at idle?

[StuntCock]

Thanks for your reply. Fine at idle, and fine with larger throttle opening. It is worst at light throttle - about 1400- 1500 revs 10-12 mph in 2nd for example has it lurching like mad, particularly over bumps. It’s like you physically can’t hold your foot steady enough (but my previous 2,4 tcdi’s didn’t do this). Thanks.

[100SRV]

Is this in low or high range?

I believe that from TD5 onwards there were two different responses to accelerator inputs, a steep rate in high and gentle, more progressive in low range. Perhaps, if you are in high range this is what you are experiencing?

[StuntCock]

Yes, this is in high range. I believe you are correct about the throttle response being linear in low and a 30% step in high, however previous TD5 and 2.4 tdci didn’t do this, hence looking for the reason this one does. I could use low box but that is working round the issue not fixing it.

[Bill]

Have you tried resting your foot against what ever is solid to the right of the pedal? That can help stabilise your foot and stop the bumps throwing it around so much.

[camel_landy]

By way of comparison, have you tried it in 3rd/4th Lo, instead of 2nd Hi?

Do you know if the previous owner had a remap?

M

[StuntCock]

Thanks for the replies. It is much better in low box 3rd/4th/5th which does indeed point to the map. I don’t know if it has previously been remapped. I guess if there was a map available that had a more gradual % throttle opening like in low box that would help. I did consider if it’s possible to fool it int thinking it’s in low all the time, but then I guess the tick over would be raised all the time too?
I suppose I’m hoping someone will say ‘ah, the widget is bust, fit a new one and she’ll be fine’. But perhaps it’s a case of ‘oh yes, the 2.2s all do that’?

[100SRV]

Is there one of those plug-in "remap" things in the OBD port or RH seatbox?

[StuntCock]

Just checked. Nothing plugged into the OBD plug, nor anything unusual under the drivers seat. Thanks.