Someone who knows their Civics...Help me out!

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A few months ago, I did a swap in my 2003 Civic LX.


2003 D17---> 2001 D17 Vtec
2003 D17 Wiring harness----> 2002 JDM D17 Vtec Harness
2003 Lx ECU ----> 2003 SI ECU

For the first few weeks, everything was great...until I started noticing something was up with the elecrtical system.

Some of the things that have been going on;

1) There is always feed in the aftermarket stereo, which there wasn't before. I rewired it, put new RCA's, regrounded everything in the stereo...Nada, still feeds.

2) Somedays (especially when it's cold+damp out) my car wont start. It turns over fast, there's definetly fuel...but it never starts. I have to plug in my OBD2 scanner, reset the computer and then it fires right up.

3) Sometimes when I come out of a car wash, the radio SCREAMS. Probably one of the loudest sounds I've ever heard. Not to mention that the highbeam light sort of flickers sometimes when coming out from a wash. Goes back to the normal feed after a day or so of driving.

4) When stuck in traffic/driving at low speeds, the "key" light in the dash flashes. The little green key will flash inconsistently and the volts go down to 12 and stay there, regardless of RPM'S. Once I get moving again for a while, it goes away. Volts go back to 13-14 ish, and the key light goes away.

5) Possibly completely unrelated, but one of my 02 sensors aren't working...again, it's probably just wired wrong.

6) The car always runs great. Idles like it should, accelerates like it should, etc. etc. Although, when I first did the swap, there was this one time where it was idling at 2000 and overheating...although that only happened once so? it possible these are all being cause by a short?

Is my computer faulty?

Are all these parts not made to work together? I was assured they were...but ???

Any input is appreciated!
I'm not positive how the models are in the states, but does it goes;


Because in Canada it goes


Therefore, the ecu I'm using is designed to run this engine.
Oh, ok, didn't realize you were from Canada, sorry. Try checking some of your engine wire harness grounds and check for exposed wires or loose connections. Sounds like something isn't connected properly.