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Pulsing lights by newfiejeff
Started on: 05-25-2014 06:05 PM
Replies: 13 (172 views)
Last post by: Spoon on 05-26-2014 10:03 PM
newfiejeff
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Report this Post05-25-2014 06:05 PM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
Hey all, if its not the oil burning it's something else. What causes the lights to pulse when idling or driving?
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msrservices
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Report this Post05-25-2014 07:12 PM Click Here to See the Profile for msrservicesClick Here to visit msrservices's HomePageSend a Private Message to msrservicesEdit/Delete MessageReply w/QuoteDirect Link to This Post
When you say pulse, you mean that they are going brighter and dimmer?


What happens if you have the lights on with out the car running?

My first guess is alternator.
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newfiejeff
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Report this Post05-25-2014 07:16 PM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, the lights are pulsing(dimming and getting brighter), really quick, it's like the voltage is getting higher and lower, but really quick.
Will check with a meter and try another ground
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newfiejeff
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Report this Post05-25-2014 07:35 PM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
Just checked, the lights are pulsing really fast. I put the headlights on and the pulsing is slower and about every 3 to 4 seconds the pulsing stops and becomes normal for about a second or two and then it comes back again. I put another ground on the battery and never made no difference. I put the meter on when I had the headlights on and the voltage was pulsing around 12.5 volts and when it became normal the voltage was around 14.5 volts

So could it be the battery or the alternator?
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seajai
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Report this Post05-25-2014 07:41 PM Click Here to See the Profile for seajaiSend a Private Message to seajaiEdit/Delete MessageReply w/QuoteDirect Link to This Post
Sounds like a voltage regulator. Are the lights on steady when the engine isn't running?
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newfiejeff
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Report this Post05-25-2014 07:46 PM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yes, they are steady with engine not running.
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fierofool
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Report this Post05-25-2014 08:30 PM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageClick Here to Email fierofoolSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
The alternator/voltage regulator was the cause of those symptoms in our 88 coupe. The headlights flashed similar to the way a motorcycle headlight pulses. If I remember correctly, it was putting out something like 15.5 volts.
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newfiejeff
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Report this Post05-25-2014 08:35 PM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
That was a remanufactured alternator I put on about 1500klms ago. Go figure...lol!!!
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fierofool
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Report this Post05-25-2014 08:53 PM Click Here to See the Profile for fierofoolClick Here to visit fierofool's HomePageClick Here to Email fierofoolSend a Private Message to fierofoolEdit/Delete MessageReply w/QuoteDirect Link to This Post
The one I had still have, was new from Ebay but it had been bought and put on the shelf and not used quickly enough to discover the problem and return it.

[This message has been edited by fierofool (edited 05-25-2014).]

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Bloozberry
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Report this Post05-25-2014 08:59 PM Click Here to See the Profile for BloozberrySend a Private Message to BloozberryEdit/Delete MessageReply w/QuoteDirect Link to This Post
 
quote
Originally posted by newfiejeff:
I put the meter on when I had the headlights on and the voltage was pulsing around 12.5 volts and when it became normal the voltage was around 14.5 volts.


If the alternator were working correctly, the voltage should remain constant at about 14.5V. Since it's dropping down to 12.5V that means the alternator is cutting in and out and causing the car to run on battery power.

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newfiejeff
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Report this Post05-26-2014 04:02 AM Click Here to See the Profile for newfiejeffClick Here to Email newfiejeffSend a Private Message to newfiejeffEdit/Delete MessageReply w/QuoteDirect Link to This Post
That is what I am expecting it to be. I will have to get one and swap it out, it is still under warranty(3years). The worse part is the location is not ideal if I can remember, but that it's.

Thanks again!!!
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theogre
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Report this Post05-26-2014 09:27 AM Click Here to See the Profile for theogreClick Here to visit theogre's HomePageSend a Private Message to theogreEdit/Delete MessageReply w/QuoteDirect Link to This Post
Alt is likely bad...
but See my Cave, Alternator Sense

plug or sense wire with problems then can look like alt is bad.

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The Ogre's Fiero Cave (It's also at the top and bottom of every forum page...)

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Blacktree
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Report this Post05-26-2014 10:35 AM Click Here to See the Profile for BlacktreeClick Here to visit Blacktree's HomePageClick Here to Email BlacktreeSend a Private Message to BlacktreeEdit/Delete MessageReply w/QuoteDirect Link to This Post
Yep, pulsing lights is a classic symptom of a failing alternator. But just to be thorough, you should also check the battery terminals for looseness or corrosion, and check the ground strap(s) to make sure there's a good connection on both ends. Also check the power distribution block next to the battery, to make sure the connections are tight.

Best of luck!
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Spoon
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Report this Post05-26-2014 10:03 PM Click Here to See the Profile for SpoonSend a Private Message to SpoonEdit/Delete MessageReply w/QuoteDirect Link to This Post
The last time I heard that problem the guy was clipping his power amp.

Spoon

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