AWG Selection for Honda

Which awg is best suitable for a Honda wiring harness? 18, 20, 22? Thank you in advance!

You are asking a very open question here and the selection of wire gauges depends on quite a few factors. For an engine harness these are the most common sizes, yes.

If you are also building a chassis harness you'll probably need some 16 and perhaps even 14 AWG wires for some high current components (lights, fuel pumps, etc), depending on the length of these connections.

You can use this calculator to get an idea of suitable wire sizes. You can integrate this calculation into the excel sheets you use to design the harnesses. It's not that hard to do as it is simply the application of Ohm's law. The wire resistance per foot can be found in the relevant datasheets.

https://www.wirebarn.com/Wire-Calculator-_ep_41.html

Hope this helps!

22 awg for most sensors, 20 awg for individual coils, and vvti solenoids. 18 awg would be used when you combine the power for multiple coils.