Engine Light on Reading no Throttle Body

[Bz Kn33z]

Hello. I took my car to a mechanic because the cars idle was real bad i just put a second hand engine in and replaced alot of things. So the mechanic put it on a computer test and the only bad thing that came up is that there was no throttle body reading. no volts or anything so he told me to change the TB position sensor so its not reading the position of throttle or anything. bought a brand new 1 and engine light still on same thing so is it a break in the wire? computer? i put a test light on the 3 wires and only 1 read if that helps. thanx

[Doctor Bob]

the wire that shows voltage is the 5v supply there is an earth & a signal, make sure the terminals havent been damaged by you jamming the test light into them.
plug it back onto the TPS & put a multimeter on the signal wire turn the ignition on & measure the voltage, if it changes find the same wire at the ECM & make sure it changes, if it does the ECM is toast if it doesnt the signal wire is broken.

Rob