Brian2006

iTrader: (42)

There was a thread up not to long ago with my identical situation but search owns me and I can't find it to save my life.

Here recently, my voltage has been reading pretty low... Between 12-13 volts compared to 13.7-14 where it should be. It'll fluctuate sometimes especially at idle and will drop half a volt when I roll the windows up/down. I put in a mild 10" sub/amp here recently but this problem has been happening from a little before that. I don't think it's the battery because I just had it out and charged it and the problem still persists.

Everything operates as normal and the car cranks just as it should and no problems are apparent... only a voltage gauge reading really low. Every now and again the PCM is reset kinda like the battery died (but it actually didn't) and the needles will max out when I start her.

What the hell is the problem? What are the best ways to check? Thanks!

99Bluz28

iTrader: (35)

Does the battery go dead easy when running your stereo for a short amount of time with the engine off?

Do you have to put the battery on a charger often?

Are you running a under-drive crank pulley?

It sounds like the battery might have a dead cell, I had a very similar problem with mine before; and the battery would only take a partial charge.
IMO, Do the "Big 3" after you fix your problem.

My solution; Optima yellow top battery, "Big 3" wire upgrade with stinger 1/0 Gage wire, then I also installed a powermaster 200amp alt, and a tsunami 3 farad cap. Yeah, I went overkill, but I just wanted a piece of mind knowing that problem was behind me now, for good!

Brian2006

iTrader: (42)

The car used to sit for a 2 or 3 weeks at a time while I was at school and then this problem slowly started to occur. I took off the sub power wire and the problem still persisted. Just measured the battery by itself and it was reading 12.4 volts

The sub is a really mild sub... nothing big at all

phantomzer0

iTrader: (17)

Sounds like the battery to me man. I would take it and get it swapped out for something new and just rule it out right away.

Brian2006

iTrader: (42)

Not the battery. Just had it tested and its fine

Danny2tek

iTrader: (1)

Mine started to do this recenly, but I believe it is due to the hot *** weather we are having down here lately. When I drive at night when the temp has cooled down some everything looks good.

Brian2006

iTrader: (42)

That's definitely not the cause here because this will be my 4th summer to have the car and this is the first time it has done this

The Guz

iTrader: (8)

Hows the alternator? I

Brian2006

iTrader: (42)

That's my next concern. I haven't gotten under the car yet to check it with a multimeter. What exactly should I check?

Also I have been checking the voltage reading from my passport radar detector and its spot on with the voltmeter in the cluster

nd4spd22

iTrader: (6)

yea it sounds like it may be the altenator, it does some crazy **** before it starts to go.

Dimitri-

iTrader: (10)

Alternators are funky.. my problem now (thats hopefully going to be fixed) was the connector wasnt fulling hitting the alternator plugs and that one wire was loose. And during then I HAD to drive to work for the 2 days for the new plug to come in. I was running off the battery till it got to about 8 volts. (Driving as fast as I possibly could to make it before the battery dies on me while driving) The alt wouldnt even kick in sometimes unless I wiggled the wire and even then it wouldnt stay.

So I connected the new plug, voltage went up.. a bit. Turned on AC, radio, rolled down windows.. and down it went. I just got a new alternator, going to be installing and I think that will be it.
Problem could be similar to yours so

Brian2006

iTrader: (42)

This may just be all in my head but here goes.

When I put the sub in, I put one of those brass tsunami battery terminal bolts on the positive post. Well, it kinda stripped on me and I just put in a different type of terminal bolt that had a little spacer to go in the battery cable. The car seemed to read normal voltage. With just driving around town, it hovered between 13.4-13.6 volts with the lowest reading of 13.2. I haven't driven it around much more to see if the problem is actually fixed, but could that previous terminal bolt create resistance from a poor connection causing a loss in voltage?