Bad alternator?

So I have another question for you guys, sorry for all the questions lol

So the car has felt fine since I thighten down the battery connections, but my flashpro keeps showing me a voltage fluctuation while drving for example, I took the car for a drive today, and sometimes while I was driving the car would be between 14.0-14.3 volts while in neutral and while in gear giving it gas.. But sometimes it would go down to 12.1-12.8 while in gear and giving it gas, and it would slowly get back up to 14 at a red light, but sometimes it would stay at 12.3-12.7 at the light and even after putting the car back in gear and the again while in gear it would climb back up to the 14.3.. Oh and another thing I noticed is with the a/c on (the fluctuation would happen with ac off) with would stay at the 14 range and not go down any lower.. So my question is, is this fluctuation normal while a/c is off and driving? Or whats going on? Everyone says the battery and alternator are fine and Ive never had any starting issues.

Normal charging shouldn't exceed 13.7-13.9 for a normal fully-charged battery. The 12.1-12.8 while giving it gas implies there is/remains an intermittant in the sensing circuit that's either turning down the alternator output, or not reading it correctly. The alternator seems to be okay as it's capable of outputting 14+ volts when requested. Assuming the connections to the battery posts and the (big) battery cables are now fixed, you need to check the "little" wire connections - most likely where you've worked in the battery area when you installed the intake. Recheck everything in that area first. All wires must be clamped or, better yet, soldered or cast into the connections - just twisted, taped, or wire-nutted together won't work, for long. Ignore the high voltage with AC on for now - it should be "fixed" when you tighten up the sensing lines. And the belt residue and "shaking" is likely from the alternator cutting in and out (no-load to max output) in response to the "loose connections" both battery clamps and sensing circuit.
 
I would agree after driving my car for a few hours and never exceeded 12.8v commanded while cruising. When doing pulls it would spike to 14v+ more likely to give injectors, vtec solenoids, etc. a proper solid votage to do their job. After the pull and starting to cruise it took maybe 30 sec tops to drop back to 12.4-12.6v steady. With or with out a/c on it stayed in that range.
 
I would agree after driving my car for a few hours and never exceeded 12.8v commanded while cruising. When doing pulls it would spike to 14v+ more likely to give injectors, vtec solenoids, etc. a proper solid votage to do their job. After the pull and starting to cruise it took maybe 30 sec tops to drop back to 12.4-12.6v steady. With or with out a/c on it stayed in that range.

I may be "all wet", or old school. Your readings may be "normal" as Honda may now be using a dual mode charging system.
If so, the loose battery clamps were your only problem.
Check out this article http://opensiuc.lib.siu.edu/cgi/viewcontent.cgi?article=1011&context=auto_pres
 
I don't think it's a dual mode charging but could be. I use Torque Pro app to get my info and I was looking at the value that was commanded by the "charging module" or whatever module controlled it. The ECU wasn't demanding an increase until a need was seen, mainly wide open pulls. With the a/c being on I believe the ECU knew how much to ramp up the alternator demand to not exceed the 12.4-12.6v but still able to output the amperage needed to supply the system.

I am throwing my guesses out there with my personal experience attached so I may be very wrong but I think most new cars have control over the demanded amperage a lot better than cars even from a decade ago.
 
I don't think it's a dual mode charging but could be. I use Torque Pro app to get my info and I was looking at the value that was commanded by the "charging module" or whatever module controlled it. The ECU wasn't demanding an increase until a need was seen, mainly wide open pulls. With the a/c being on I believe the ECU knew how much to ramp up the alternator demand to not exceed the 12.4-12.6v but still able to output the amperage needed to supply the system.

I am throwing my guesses out there with my personal experience attached so I may be very wrong but I think most new cars have control over the demanded amperage a lot better than cars even from a decade ago.

Not sure but I think dual mode is "new school" - the ECU decides what's needed -- You're likely fine. After a few days of no issues (lights flashing & error messages) reconnect the amp and see what happens.
 
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