Hello this is adrian, I recently bought a 93 fd single turbo. having some fuel cut issues and 4500 rpm the car starts jerking. took it to a friend said he can fix it , messed with the commander and now the car stays at low rpm 500-700. I checked the idle setting on commander and they are on 900. what could it be? Before he messed with the commander it was idling perfect at 1000 rpm had no issues with that.

set up: 93 fd bridge port
single turbo t61 power fc