Limp mode

Hi I bought a discovery 3 07 plate last week. Test drive went well. Two days later car started going into limp mode under 30 mph. The dash lit up with suspension lowering and raising fault. An f and transition fault limited gears available. We put it on diagnostics which pulled edr valve fault ( it had the parts to this capped off with makeshift blankers) we replaced these with landrovwr ones. This made it worse no power at all could barely get to 20 mph on the flat ! Went for a remapbas advised guy was brilliant and wouldn't take money as his machine pulled up nothing that a remap would sort. He noted sensor or fuel injector? We disconnected sensor and all was fantastic fir a good 5 days. And now just as we thought problem was solved here we are again. I'm literally getting 200yards down the road until I've got to turn engine off. Open \ close car and set off again on my next 200 yqrd drive. Very frustrating and quite dangerous on ynese twisty country roads. Advice gravely appreciated. Oh ive noted low power mode is this related