help me? i have a 1996 n reg toyota previa 2.4 gl auto uk model and the engine went on it . so i changed the engine and box used my gearbox and my wiring but the engine i used came out off a 1993 toyota previa but all the switches etc were the same . it starts and drives fine but it changes the gear at 5000 revs which it wasnt doing before . on the throttle body there is a clip with 4 wires if you disconnnect that then the gears work fine but not the overdrive i have changed the gearbox as well and still doing the same does anyone outther no what it could be the wiring on the throttle body is called tps wiring . please help me some one i am desperate

Sounds like the computer is confused from the 1993 sensors you have on that engine. May need the 1993 computer, or switch all the sensors to match the 1996 computer.