Howdy..
since my build, my car has never seen decent voltage at the drivers gauge.
We replaced everything and it still has issues, now they have become more aggressive. I cant seem to keep the car running well, and this voltage issue is getting dangerous.

Its no longer "maybe its just your gauge dude"
pulled strong until i revved it, then voltage dropped to 12..let off the gas.. let it idle, back up to 14ish.
i just replaced this battery w an Optima, still has the same result.. measured all this at the battery and its matching the gauge inside..


Ive noticed that anything w a decent draw exacerbates the sypmtoms, ie AC fan, headlights, etc etc.. it used to dip lower as usually expected, but DAYMN. .now its just BANG, down to 12....

BUT.. i can drive down the road at 13ish as long as nothings really "on" and im staying in low RPMs.

The alternators we keep swapping all test good when out of the car.

w...t....f



here's the deets, car has 105k miles on it..
had OEM alternator in it after build was done, since replaced w a OEM spec TYC alternator
New DAYCO belts
new 1 gauge big 3 power wires.
Nothing fixed the issue.


Tested the Oreillys battery yesterday.. was fine..

tested new optima battery it was fine.

 

Do you have a broken engine mount ? Check/clean/replace the connector to the alternator.

I had an intermittent problem with alternator erratic output caused by faulty connector due to a broken engine mount in my CTS-V; engine rocked too much and pulled on the connector but not enough to cause a damage visually. I replaced the pigtail.

 

Nope.. my (car) problem is just as fking weird tho Lol..

Had my budfy Ivan ( GTR Nissan master tech) trace it from the column gauge pod all the way out to the pos boat anchor tyc alternator Lol.. it literally just had THAT as an internal problem... never had an alternator do this dance before..evah... so this is me posting back so folks know for the future..if your alternator does this..you're not crazy.. get a new one and be done..

I'm going to reinstall my OEM alt for now and am talking to DC Power in riverside about a fully billet ***** to the wall 180a at idle masterpiece.

 

So the voltage regulator was bad? Sounds like it since its built into the alternator.

 

I have a similar problem with my 2003 Z. With out the lights on the car will run around 14 volts. Turn the lights on or hit the brakes voltage drops half way btw 12 and 13. Totally list I too replaced the battery and the alternator. Think I may have to do it all over again to solve this problem.

 

i have same problem on 2008 350z started at around 110k miles.. i bought a new battery, then today installed a new alternator and the volt meter on dash doesnt move as much, only moved once.. check out my thread

 

If you're running putting a large load on a battery by running an accessory (i.e., high-wattage stereo) in series as opposed to in parallel, your ECU can be blind to the added load on the battery and you'll get a voltage drop to the point where your engine will cut out. This can also happen if you re-locate your battery to the trunk and ground to the rear chasis (you're going to get too much resistance).

The first thing to do if you're getting a severe voltage drop is to check all your main power and ground connections from the battery. Clean the connections and make sure everything's nice and tight. A carbon pile load test will do a good job to tell you if your battery is bad and your alternator can be tested with a simple volt meter at the battery terminals.

 

Forgot to update..
The upgraded wire I used 1
(0 ga stereo wire) was JUNK..

CCA.

Never even knew there was such a thing..horrible stuff.

Melted..nearly caught on fire..
Swapped to pure copper welding cable w fantastic crimps and soldering. Good to go now w the old OEM alt.

Sent from my DROID RAZR MAXX HD using IB AutoGroup

 

Good to know...I know you had previous issues with the some high amp alternators as well; you think the wiring issue was the problem all along or do you think the aftermarket alternator was an issue as well...

 

I just wish I could drive the car and not worry about the voltage gauge dropping to almost 12. I have no idea why it drops bu ta new alternator and battery I still loose a bit of voltage when I hit the brakes with light on. It is really weird...