Your alternator is going bad. There should be zero voltage fluctuation when an electrical load is introduced. I just replaced mine at Napa the other day. 80 bucks after core with a lifetime warranty. Well worth it imo.

 

Depend on what you turn on but 0.1-0.2V drop is normal during initial surge as the ECU raise RPM to support the load, sometimes it will recover but some might just stay that way but it is normal. My Camry drop nearly 1V when I fire up the quad HID retrofit but it will recover about 0.8V after, that's ~15A to fire up those bad boys

 

I just checked the alternator and its putting out plenty of power at idle. Could it be the oil pressure sending unit? I checked the ground of the sender and at idle it has about .7v going through it but when the headlights are on it drops to .58v, could that be what is causing the fluctuation?

 

I just checked the alternator and its putting out plenty of power at idle. Could it be the oil pressure sending unit? I checked the ground of the sender and at idle it has about .7v going through it but when the headlights are on it drops to .58v, could that be what is causing the fluctuation?

 

Never mind lol my alt is not good. It had less than 9 volts coming off it when the car was on

 

https://www.rx7club.com/market/1156628

 

alright so I got it tested and they got it up to 70 amps and said it was fine even under load. Does that mean it's a ground?

 

Or maybe the voltage regulator?

 

You'll have to start pulling fuses to isolate the problem, basically disable system one by one to see which one is dragging the whole system down.

 

ill do that. Im thinking it might be the engine fuse (in the interior fuse box) since that was where i was originally pulling the power for the gauges, and since I removed the fuse tapper i just replaced it with the exact same fuse but I will see tomorrow

 

Could it be that I'm using 22-24 gauge wire for the information sending wire? Like it is losing voltage through it or something?

Nevermind... My stock gauges are also suffering from the problem, I don't think its anything that has to do with what I did to the car in terms of wiring.

 

I apologize in advance if I come across as rude, but this thread was painful to watch and read through when the solution has been in the Second Generation FAQ since before I joined 15 years ago. My post in your other thread referenced the article written by Aaron Cake that spells out exactly what is going on (Ohm's Law). I just went into detail about how it alters sensor readings and affects sensitive circuits.

A stock "70 amp" alternator will put out about 40 amps on a good day and will fail if you look at it funny. Pretty sure they're measured in Chinese amps, not real ones...

Also, how to use a relay is literally a google search away. This is a good resource for beginners to bookmark, chick full of how-tos and such that cover all of the basics to handle wiring matters correctly:
https://www.the12volt.com/

Anyway, read up on what I've written, and on the12volt, and you'll be on your way to straightening out this mess.

 

You are good man haha doesn't hurt my feelings any. I appreciate the help.