Looking for a little insight from those with more wiring experience than me. This is a subject I've tried to do some searching on, but haven't found much of a solid answer. So instead of assuming this won't be an issue I'd rather ask.

Been working on my gen 3 LS swap for about two years now. I started with a truck harness and have most all of it done at this point minus running all my main powers and grounds in the engine bay.

More specifically I want to run the charging wire from the alternator in the same loom as the injectors/sensors, the idea is to keep everything as neat and clean as I can.
On newer cars I've seen this done with no issue, but also I've kept in consideration that newer electronics are probably better at filtering out interference/noise.
As of right now the experience I do have with 12v circuits and common sense tells me that as long as I have solid grounds I should be okay.
Is this correct?

 

It's 14.6v DC, so there's no reason it should cause a problem. You should never run AC right next to DC or signal wires...

 

Ideally you would not want to do this...

However, I will say that it is far less of a concern with an OEM PCM.

For anyone that is using an Aftermarket PCM/ cares about accurate Data/ can't afford any "Hick-Ups" at the Track...
Avoid do this.