Either wires or computer if TPS has been replaced.
TPS(throttle position sensor) is just a variable resistor, like a light dimmer or Volume control, so easy under stand how it works.
Computer sends TPS 5volts on the top wire, TPS sends back lower voltage on center wire.
Lower wire is a Ground.
When throttle is closed center wire should read .7 to .9 volts, when throttle is wide open then center wire should read 4.5-4.8volts, so as throttle opens voltage on center wire goes up.
Just like turning a light dimmer increase voltage to the light bulb.
Computer has a 5 volt power supply, it can fail, code 63 "Throttle Position Sensor (TPS) signal too low"
Or wire can get corroded, lowing voltage.
Power supply can fail with higher voltage, so it has 6volts instead of 5volts, then you could get code 53 "Throttle Position sensor too high"
Or wire could be shorted to a 12v wire.
Could even just be a misadjusted TPS.
Use a volt meter set to DC volts
Use sewing pins to pierce top and center wires so you can test voltage
Turn on key
Put meter's black probe on a Ground
Touch Red probe to top wire pin, should read 5volts(4.7-5.0v), if it doesn't then you found the problem, this voltage is the Reference voltage, so no need to test anything else if this is wrong.
If you have 5volts then test center wire, should read .7 to .9volts(under 1volt), if it is higher or lower loosen the TPS screws and turn sensor.
If it won't get to the proper range look at the throttle linkage, you will see a screw, it "looks like an idle screw", it isn't, it is to adjust TPS and prevent dieseling(run on).
Adjust the screw to get proper closed throttle voltage on TPS.
Now slowly open TPS and watch center wire voltage, it should go up steadily, no jumping around, at wide open throttle you should see above 4.5volts.