The 2wd should be around 5V at idle, and 0.5V at WOT.
Maybe it has a 4wd tps ?, this would be around 0.6V idle, and 4.5V at WOT, if not have the outer wires in the tps plug been reversed as when fitting a 4wd ecu/tps to a 2wd loom.
At the moment your ecu will be going fully rich as soon as you touch the throttle, and progressively leaner as it's pushed further.
tabetha