How does cables and wiring affect my engine?

Usually any type of engine need to communicate with the components of the engine and with eachother and the way to do that is through cooper wires that relays all the paremeters to the sensors, the ecm has pins and each pin is for a designated area or part of the engine to work properly, usually whenever there is movement and the harness is loose from a part it will cause friction with the other cables or components of the engine and create resistance although it doesn't happen often but sometimes the only thing that stops your engine from working properly is a little wire that is important for communication, it is a very time consuming task since there are a lot of pins on the ecm and each pin sometime branches of on the wire separating to go to another similar component, inspecting all of them to know which might be the cause can take up to more than 3 hours but often time it can take more depending on how bad it looks it would be better to get a new wiring harness but the problem with that is that sometimes they can be a tad expensive.