Lights dim when rpm drops
#1
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Lights dim when rpm drops
Ever since I've had my 993, the headlights dim when the revs drop. It doesn't particularly bother me, but I wondered whether it was a sign of something screwy in the electrical system. Any ideas?
Thanks,
John
Thanks,
John
#2
Three Wheelin'
Unfortunately, it sounds like its your altenator going south on you (in a bad way)
If thats the case, rebuilds with a core charge/refund is the way to go IMO.
If thats the case, rebuilds with a core charge/refund is the way to go IMO.
#5
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John,
Where are you located? If nearby, I'll gladly help install the new alternator. I just replaced mine with a Porsche-rebuilt unit that I purchased from Sunset. Cost was $290 (I think) with a $40 core charge. Unless you have debilitating OCD tendencies like me, the swap is fairly straightforward and should take a couple of hours at most.
Andreas
Where are you located? If nearby, I'll gladly help install the new alternator. I just replaced mine with a Porsche-rebuilt unit that I purchased from Sunset. Cost was $290 (I think) with a $40 core charge. Unless you have debilitating OCD tendencies like me, the swap is fairly straightforward and should take a couple of hours at most.
Andreas
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Thanks everyone! The weird thing is that it has been this way as long as I can remember. I'm thinking that as it gets worse, I'll eventually get a dead battery, right?
Thanks,
John
Thanks,
John
#7
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Hmm. That's not what happened when my alternator died.
The alternator charges the battery and the car's electrical systems run off of the battery. I would check the battery as it seems it's not putting out (hmm, did I every date your battery) and the battery is not holding the charge.
The alternator charges the battery and the car's electrical systems run off of the battery. I would check the battery as it seems it's not putting out (hmm, did I every date your battery) and the battery is not holding the charge.
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#12
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It sounds like a battery rather than the alternator. If you have a RS pulley system (look at your fan on the engine...does it have one belt or two running to it?). If it has just one you likely have an RS pulley so then its common that the lights dip since on idle the alternator does not spin fast enough to keep up with the current draw.
If you have two belts the alternator should keep up with current draw on idle if the battery is in good shape since its used for supplemental capacity. If its not holding a charge very well the battery may not supply enough supplemental current and the lights dim.
Cheers,
Mike
If you have two belts the alternator should keep up with current draw on idle if the battery is in good shape since its used for supplemental capacity. If its not holding a charge very well the battery may not supply enough supplemental current and the lights dim.
Cheers,
Mike
#15
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Hmm. That's not what happened when my alternator died.
The alternator charges the battery and the car's electrical systems run off of the battery. I would check the battery as it seems it's not putting out (hmm, did I every date your battery) and the battery is not holding the charge.
The alternator charges the battery and the car's electrical systems run off of the battery. I would check the battery as it seems it's not putting out (hmm, did I every date your battery) and the battery is not holding the charge.