Need help starting and electrical problem. Alternator?

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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My car battery keeps on getting drained overnight,no lights no digital clock. At first even tho i jump start it it still doesnt work so i hacksaw and replaced the termimal. Then i tried to jumpstart it and it worked then i left it overnight my battery got drained again. So i jump start it again took freeway,when i got off i start the car and it started took it off and got drained overnight again. So everytime i drive it for awhile it wiil run. My battery is new i even tried to recharged it couple times already.everytime i jumpstart it, it is hard to start. It even feels like when the car is running its having hard time to run or get power and sometimes when on idle its rpm goin down its like the car will die( one time it did died) Espcially when i pump the gas pedal while idle. also sometimes when i try to start it the the digital clock on dash gets dimmed and also dash lights until it will gone when i try to start it repeatedly(without jumpstart) everytime that happens if u start it there wont be a clicking sound and no crank and dashboard gets dimmed and gone. I know i have a problem with starter i had it for long time i have to try it few times it will just click but it will start. I have check engine light but the machanic told me its ignition coil i had that too for long time my car starts and run. My battery got drained before because of grounded wiring on hid so i took it off replaced it with normal ligts and its good again. And now im having problems again, could it be alternator failing or battery cables? Pls help me with these i tried to research but still not getting answers. Thanks!


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S13_RB25
Posts: 556
Joined: Thu Jan 14, 2010 5:20 am
Car: A 240 but no RB yet!
Location: Burlington, NJ

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Does your battery light light up on the dash? Also instead of jump starting the car everyday, take one day and take the alternator to autozone to get it tested! And if it is dead its another excuse to buy a quest alternator, its 110amp and cheaper than the stock 80amp one! :) Gl

Sn4zzle
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Joined: Thu Aug 18, 2011 6:40 am
Car: None :(

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Definitely not the alternator. When an alternator is bad the battery will not get enough spark to start up. The alternator is not going to drain the battery (at least not from what I have seen). The alternator may need replacing, but it is probably something else. :whistle:

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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I might take it to shop tomorrow,i just wanna get some idea so i wont be ripped off. Would it be possible that it is still running because of the power it got from the jumpstart. Because at first it runs good even on idle but after a minute rpm will drop and struggling to run and get power? but i have a slight feelng its alternator, if not something is draining my battery and im having difficult time to find. It cant be the starter right?or ignition coil?

You mean nissan quest van alt? On s13?

And thanks for the info!

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S13_RB25
Posts: 556
Joined: Thu Jan 14, 2010 5:20 am
Car: A 240 but no RB yet!
Location: Burlington, NJ

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Im leaning towards the alt too! Since that is what does the most work after the battery helps start the car! Also yea the nissan quest alt, if you do get it, get it from the year 1997! The only thing you'll have to do is drill out the bottom holes a little bigger for the bolt to go through! Also im assuming that you still have the ka? Cause it doesn't work on the sr!

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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Yea i have ka, it wont gonna overcharge or sumthing like that right? that will mess up something like the computer and sensors on the car.
I wish i have an sr tho lol.

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S13_RB25
Posts: 556
Joined: Thu Jan 14, 2010 5:20 am
Car: A 240 but no RB yet!
Location: Burlington, NJ

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Nope it wont over charge or anything of that sort!

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Armstec_S13
Posts: 404
Joined: Wed Dec 20, 2006 6:03 pm
Car: S13 Coupe

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Any aftermarket electronics? Alarm, stereo, amp, gauges, also maybe the battery has a dead cell or maybe your brake light switch (dunno? Notice if your break lights are on after you get out?) just trying to honk and help

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Armstec_S13
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Car: S13 Coupe

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Think^

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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I got hid but i already took it out last june this year, the wires of hid are grounded and discharged my battery and after i took it out its all good. I got led domelight and i took it out its still not solving the problem, i check all the lights makin sure i turned it off before i leave the car. I was thinking beside alt is battery cable.

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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my battery is couple months new i even had it checked and recharged so many times even its new. I dont have any other aftermarket parts besides the hid and dome light

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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Im thinking about fuses how would i know if the alternator fuse is blown if im not mistaken i could just see without removing it, its the metal thing like the one on 20 & 10 fuses? And i also wanna kno whats the voltage regulator looks like and where it is. Thanks!

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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so i bought a multimeter
Before jumpstart(didnt use for days): 6volts
After jumpstart but turned off after a minute: 11-9v
Engine on:14v
Drove it for 20 mins: 13.7v
engine off key turned on: 12v
Engine off and key turned off: 12v
and now i'll gonna wait overnight if it drains.
I took out the head lights fuses.

So if my engine is turned on and its reading 14-13.70 volts,my Alternator is still working,ami right?

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S13_RB25
Posts: 556
Joined: Thu Jan 14, 2010 5:20 am
Car: A 240 but no RB yet!
Location: Burlington, NJ

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Yea that sounds about right!

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amanoma
Posts: 37
Joined: Thu Jul 15, 2010 1:45 am
Car: 91 240sx
Location: Fremont, CA

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i checked it last night after five hours the voltage droped. every 50-40 seconds it drops .01 volts.
I just checked today, its roughly at 12v
I tried to start it and its hard to start but it started after few attempts. Then i shut it off checked it and its dropping .01v every 3-10 secs.
Could it be the voltage regulator?
I might change the alternator today,i hope it will fix it.


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