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Voltage Fluctuating And Headlights Pulsating

lineskee 33

By lineskee 33,
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lineskee 33 Community Regular

lineskee 33

Posted
Posted

Hi all,

Im having an issue with my car at the moment and i dont know much about car electrics so im a little stumped. When i start the car at night all the lights and everything seems to pulsate. it doesnt sit on a constant 14v, it jumps back and forth between 13 and 14 volts. I can also hear it affect the fuel pump aswell. I only mainly notice it because the headlights constantly go dim and bright. Is there something like a voltage regulator or something like that that could be stuffed? if so where could it be and what can i do to fix this?

I would be forever greatful if i can get some answers.

Thanks

lineskee 33 Community Regular

lineskee 33

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cheers mate. im pretty sure its not the alternator. im leaning more towards the regulator. thing is i know what a alternator is and where its located and what it does. but haha i dont know where the regulator is. any help there?

r33cruiser Grand Master

r33cruiser

Posted
Posted

it sounds like the alternator is failing to charge the battery.

flickering lights that pulsate brighter with hi revvs is a key sign.

get a pro to look over it. odds are its the alternator or battery

lineskee 33 Community Regular

lineskee 33

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hmm. well it really pulsates when the car is idling. but i have noticed sometimes when i get it to near redline the battery light lets off a bit of a flicker on occasions.

I bought a brand new battery a few months ago, and i spent a fair bit on it. and it was happening before i got the battery. so im ruling that out at the moment. Or I should just say it better not be the battery or else.

blind_elk Grand Master

blind_elk

Posted
Posted
cheers mate. im pretty sure its not the alternator. im leaning more towards the regulator. thing is i know what a alternator is and where its located and what it does. but haha i dont know where the regulator is. any help there?
The regulator is built into the alternator. If it's suddenly dropping and rising, then I'd suggest the regulator is on its way out.

Get a sparkie to check out the alternator.

stenve Proficient

stenve

Posted
Posted (edited)

i have a similar problem too

i have a switch on my dash that when it is turned on lights up, when i rev it a bit this light dims then comes back bright when i stop the revving.

also as the fuel pump primes (bosch 040, direct wire) it doesnt sound quite right or as loud as it used to. sometimes it take the car quite a while to turn over while cranking it. its a bit anoying and worrying

could this be the same problem? alternator playing up?

guess i'll get someone to look at it

Edited by stenve
Jmaac Proficient

Jmaac

Posted
Posted

Could possibly be an earth or a mismatch b/n battery & alternator size. Most regulators actually sit on the back of the alternator (its that black plastic box) but this depends on the type i.e. hitachi, bosch etc.

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