Agonising Issues - Help

[wolaila]

Well after my X5 being into 2 garages, car is still lumpy, hesitant under load.

History

1) Vehicle has had compression test and coil packs tested and comes back nothing
2) Under different diagnostics comes up with issues under random banks

Changed the Gearbox oil

Then after that the Battery light came on, so changed the alternator, to find the battery light still on.
The car is charging fine and the alternator works fine.
However the battery light stays on.
Battery has been changed for a new one....and battery light stays on.
Unfortunately I do not have the money to keep throwing at it.
So the problems at the moment are
1) Battery light continuously on.
2) Hesitant and missing under load.
Options
Thinking of fixing - if anyone can offer any advice.
Selling as is and selling at a huge loss.
Thoughts anyone?, just do not know what to do..love the car.....but...after months of issues......I give up ..nearly...
Thanks