Stalling with full throttle

I need help. I have a 93 swift with 1.3 8 valve engine where it hesitates/partially stalls when I give it full (not necessarily to the floor) throttle. This happens both at accelerating from stop and at highway speeds.

I changed the fuel and air filter and use the injector cleaner on regular basis.

Anyone has any ideas?

double check your timing, i've had similar problems and it turned out that i was fireing after the piston was already on the war down and to much fuel just kills it, its just a thought

Throttle position sensor!!!!