battery being drained while car is running.. help plz!

[zupaspunk]

While I drive my fox my battery slowly drains.. I have a brand new 140 amp alternator (one wire), new battery. The voltage guage either doesn't read right cause it's low even with a new battery. I have an electric fan that I manually turn on/off that drops the volts initially but seems to even out after driving for a while.. I can tell it drops them cause the lights go dimmer when I turn it on. Plz help any ideas would be appreciated.

[nitrostangracin]

Did you rewire the back of the ALternator properly for the 1 wire set up?

[Wayne's 88 GT]

Welll, first I'm going to say is welcome to the SEFB boards......2nd thing is if you can tell the lights dim with your electric fans on.......I'd pull the fuse for your fans and see if that makes a diff in the voltage drop.......then I'd check the wire from the alternator wire and make sure all the connections are proper........I'm sure some of our other more experienced member will chime in soon on this!

[1sxyfox]

i agree with the above post, check to make sure the alt, is wired up right (not saying your stupid) sometimes you just over look things or forget about them, i do it all the time.

[Badass1993]

I always figured that was normal,when you switch on a ele fan,with the headlights on.......I would check voltage and get 14.5 or so with all off...and that would drop to 12.9-13.0 with the lights on and ele fan running. I was running a powermaster 140 alt,with a optima red top,black magic ele fan

[nyfreakinrican7]

Have you hooked a voltage meter to the alternator to see what it is producing with and without the fans on. From what I read about electric fans they do pull a lot of power when first turned on and they should have a relay wired in to protect the battery and alternator from damage. When did this happen after adding the fan or after adding the alternator? Re-trace all your steps. And its nice to see some people close to me for once welcome to the forum I am also new here

[zupaspunk]

Wow wanna talk about a difference from other forums I've been on. Thanks for being my new favorite forum and thx for the welcome. Yes the alternator is connected correctly.. As far as a fuse in the electric fans wiring I'll hvae to look, I'd guess it would probably be in the relay box? The fan has been in this fox for a few months already but I've consistantly had this problem with this car. I was told with upgraded pulleys that my belt might not be turning the alternator fast enough.. if so what could I do to counteract that? Gonna check and see what the alternator is putting out for volts, thanks for the suggestions gonna get right on them.

[Sphinxmunkey]

If nothings dying, it just dims the lights and the radio doesn't hit as hard as it used to :p

Then its probably the underdrive pulleys you just mentioned, if you can find a smaller alternator pulley or larger aluminum crank pulley for that extra .001 lb of rotating mass... lol I don't personally believe much in underdrive pulleys. But the only way to see if that's your "problem" is to swap it out for a stocker and see what happens.

Of course if its just dimming some and your battery doesn't die (If it does, go to advance and have it and the alternator tested) then I don't see a huge problem myself?

Maybe some more detail is needed for me to fully understand your concern? :)

And :welcome: hope you enjoy it here, lot of nice guys lol

[1sxyfox]

Ya i missed the fact that you had underdrives, and that it's self will drop the volt gauge down while the car is running i know mine did that when i put my underdrives on my car.

[nyfreakinrican7]

When I upgraded the alternator I pulled the original pulley off and used it on the new alternator.

[fiveptohhh]

im having the same problem with my car. it has been doing this since i got the car. ive replaced everything linked to the charging of the battery. it isnt that bad until i drive it at night with the with the lights on then if you shut it off it wont crank back up. will an underdrive pulley on the alternator help. my wife said i need to fix it she is tired of push starting the car at night :angry:

[nastynotchback1]

a problem i have seen alot is a person will install a 140amp alt and use the factory wiring to charge with and that wiring was not designed to handle those amps.you should always run a new charge wire and i like to use 1a/u or atleast 2ga.another thing is to realize that most high amp alt's don't produce very much at lower rpm and idle.they will produce the advertised amps at higher rpms.another thing i have seen is too small of a wire used to wire an electric fan or whatever and it causes it to pull alot of amps upon start up thus causing the lights to dim for a very short time.

[Sphinxmunkey]

im having the same problem with my car. it has been doing this since i got the car. ive replaced everything linked to the charging of the battery. it isnt that bad until i drive it at night with the with the lights on then if you shut it off it wont crank back up. will an underdrive pulley on the alternator help. my wife said i need to fix it she is tired of push starting the car at night :angry:

Have you had the battery and alternator tested? To me it sounds like the battery has a bad/weak cell or the alternator isn't charging fully... that or the starter solenoid. I'm no authority on the subject but when I worked at advance every couple days someone would come in complaining of their lights dimming car dying trouble starting, specially when cold weather hit, Idk why but it kills batteries like nobodys business.

Anyway, they all swear the battery is new but new batteries can have bad cells too. Get them checked on a diagnostic machine (voltmeters can't check dead cells or ca) my moms fiance swore his battery was good up and down, never could figure it out, voltmeter told him it was good, a week later he let me take it in and test it on the machine... no amps but a held great charge of 12.8ish volts, machine spit it out in less than 2 minutes.

There are 10 scenarios of what it could be, but we have to know all the details :)

Oh and this was happening to an rx7 I used to have (300 dollar car, fun as hell) it turned out to be the starter solenoid.

[nyfreakinrican7]

I 2nd the whole get the battery tested thing you don't really know if it has a bad cell till it is tested correctly.

[DSTRBD]

This maybe over the top but I've seen members go crazy when it was just the cable ends !

[Sphinxmunkey]

This maybe over the top but I've seen members go crazy when it was just the cable ends !

:lol1::lol1::lol1:

That is the best, it happens all the time on every forum.

I know a guy that sold a car for 1/2 what it was worth over a bad battery cable.