ok this is getting really annoying the car drives and runs starts perfect the battery is new the alternator is new there is nothing wrong no problems but the dam battery light keeps blinking and i can hear somthing under the hood every time it blinks.. it blinks about every second for a peroid of time.. if i press the gas or brake it goes away and then comes back when i let go.. its just annoying theres nothing wrong with the car but i cant stand it anymore

 

Is the battery secure? Terminals tight?

 

Get your alternator checked out.

 

Im gonna go with this one ^^^^ or a loose belt cuz you mentioned when you press on the gas. check you your batt terminals and check the 10mm nut on the alternator to ensure its tight as well

 

Lol could your alt be loose? Doubt it but hell with a check while you are in there. It could also be your sense circuit lines check that your plug is secure. Good luck

 

+1 it's your alternator

 

He said both the batt and the alt are new so it has to be a loose connection somwhere.

 

I've seen supposedly "new" alternators actually be bad out of the box.

 

You are so right, but I would start with the basics first before you pull it back out thats all im sayin

 

yup! happened to me 3 months ago take it out and get it tested at autozone

 

yeah it has happened to me as well with a starter I got from Autozone and an alternator from napa. its hit or miss sometimes with auto part stores. im just saying to rule out the other **** first before you waste your time taking it all apart. good luck man

 

well wen i got my alt tested they just plugged something to the batt n said it was good

 

Are you mental or something? They tested the battery and said the alternator was good? Did they actually test the alternator?

 

they said the alt was good but they just hooked something up to the batt idk how else to test it do u?

 

What car? A bad battery won't turn on the charging system light because this indicator light signals a charging system problem, not a weak battery.

1) Check whether the alternator belt and all alternator mount/bracket bolts are tight.

2) Get a multimeter and measure voltage across the two battery posts with the warm engine idling under no load (all electrical accessories off) versus under high load (A/C max, high beams, rear window defogger). Post those two voltage readings.

 

Yea check out voltages with a volt meter, might be easiest to get a cigarette lighter volt meter.

Keep in mind that some or all of these cars have an ELD (Electronic Load Detector (current meter)) in the fuse box and the computer will stop the alternator from outputting the normal charge voltage during certain conditions, to save fuel, such as when the car is travelling at certain MPH, engine temp, load on electrical system, whether the fuel is cut off to the engine... So the alternator won't necessarily be at the charge voltage of 14V or whatever all the time.

I'd check the resistances from the alternator to the electrical system.

 

This^ normal ELD function will NOT cause the charging system light to turn on.

 

it does seem to only happen at idle so i guess thats low charge

 

You now have several tests to do. Report back to us on the results of those tests.

 

ok well my battery voltage is jumping from 13 14 and 15 bouncing around pretty fast and something by my alt is making a high purring humming noise every half second

 

Sounds like a bad voltage regulator inside the alternator (<--- replace).

By or inside the alternator?

Also answer these questions:

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You MUST provide all pertinent information about your car and engine. Failure to do so may result in thread closure.

 

1992 civic si

 

He advised you to do this as well. What about it?
It's like pulling teeth with you.

 

also everytime the batt blinks the headlights n dash flicker at the same time

 

You must really like locked threads.