My mate's got a 99 Ka 1300,

it's only firing on cylinder's 2&3 any ideas or has anyone came across this fault before?
I suspected a sensor fault so "borrowed" a crank & camshaft sensors & coil from another Ka and it has made no difference.
It's almost as if the car's in limp home mode but correct me if I'm wrong they don't have this feature do they?
Possible wiring/ecu fault?
Any links to wiring diagrams or any readings i should be looking for?
Thanks in advance for any help/advice given!!