Transmission Issues? 95-96 318 M44-HELLLPPPP!!!

[bimmermanic]

Strange quirk on a bredrin of mine's E36. He was messing about with the shift pattern select switch whilest highway driving. Fiddling between "S" and "E". He then noticed the gear symbol on the instrument cluster and the car seemed to run rough in limp mode. He disconnected the battery and reconnected it and it ran for a while like a day then the symbol returned at the same rough lumpy idle. He took it to a tranny specialist with an obd2 scan tool and the code they pulled indicated an Accelerator Position Sensor error. Well since then all the pundits locally here in Jamaica hasnt seemed to figure what the problem is. Does any one have any idea what could be the problem? My prognosis is that internal or external tranny sensors might be stuck or problematic.... Any other ideas? Nothing will sound too wild.
Cheers!

[bimmermanic]

Any ideas guys?