It depends on the maunfacturer of teh sensor, but generally, no, you can shorten the wires if you need to. Be sure your particular sensor either has or does not have a resistor diode in the wire. If it does, you need to be sure that is left in the system, and not discarded.
Many stand-alone tuning systems (HP Tuners, etc..) use widebands, and they have a short lead with a plug. from there the include a harness withthe corresponding plug for ease of installation, but the other end of the harness wires into a programmer specific plug that you have to do yourself. You can shorten this harness without effecting its performance.
Most wideband sensors have all the sensitive stuff inside the body of the sensor, and the wires are mainly signal output, input, power, ground, etc. Some also use a tach signal, so just learn what type of sensor you have and google the instructions if you have to.
I'd be happy to help locate any information if you need it, just pm me and I'll see what I can do.
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