voltage wanders a little...is this normal?
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Pro
Joined: Aug 2001
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From: mississauga ON
voltage wanders a little...is this normal?
I noticed my dash display flicker a little while driving
last night, so I switched my guage option to Volts. This is what
I observed: cruising in third gear at about 2000 rpm, with nothing on
except headlights (no way to shut them off) the voltage reading wanders
between 13.7 to 14.6 volts. Is this normal?
last night, so I switched my guage option to Volts. This is what
I observed: cruising in third gear at about 2000 rpm, with nothing on
except headlights (no way to shut them off) the voltage reading wanders
between 13.7 to 14.6 volts. Is this normal?
Safety Car
Joined: Aug 2002
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From: SANTA CRUZ CA
Re: voltage wanders a little...is this normal? (LT4Coupe)
voltage reading wanders between 13.7 to 14.6 volts. Is this normal?
Race Director
Joined: Oct 2001
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From: Melbourne Florida
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Re: voltage wanders a little...is this normal? (LT4Coupe)
Been there, done that !...it got to where I called mine the Disco Vette.. :lol: ..my problem was the Voltage Regulator...replaced the alternator/regulator with a heavy duty 140 amp and ...Voila...all fixed...good luck
Safety Car
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From: Jacksonville Fl
Re: voltage wanders a little...is this normal? (LT4Coupe)
Your car came with a 140 Amp stock...it should have a pretty consistant voltage, but if a heavy load cycles on/off, it can cause fluctuations.
As long as your voltage stays consistently above 12.5v at idle with AC and headlights on, dont worry about it.
As long as your voltage stays consistently above 12.5v at idle with AC and headlights on, dont worry about it.
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From: Punta Gorda, FL
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Re: voltage wanders a little...is this normal? (tdock)
I get fluctuation when I turn on my blinker signal. Goes up and down .2 volts. Today, I was able to cause this:
Put car in gear, foot on brake, AC on, headlights on, and blinker on. Voltage dropped to 12.2 :eek:
Does this sound like an alternator? Sometimes it puts out 14.4 volts while driving, other times its 14.0. When I'm stopped at a light, it will drop down to anything as low as 12.8. Get going again, and it will go to 13.9 or 14.0 (sometimes + or - .2)
Whats goin on here?
Oh yeah, when the voltage drops, occasionally the engine will make this jumping sensation, or jerking sensation, but the rpms dont seem to change at all, just voltage.
Put car in gear, foot on brake, AC on, headlights on, and blinker on. Voltage dropped to 12.2 :eek:
Does this sound like an alternator? Sometimes it puts out 14.4 volts while driving, other times its 14.0. When I'm stopped at a light, it will drop down to anything as low as 12.8. Get going again, and it will go to 13.9 or 14.0 (sometimes + or - .2)
Whats goin on here?
Oh yeah, when the voltage drops, occasionally the engine will make this jumping sensation, or jerking sensation, but the rpms dont seem to change at all, just voltage.
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From: Athens AL
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Re: voltage wanders a little...is this normal? (vetteweiser)
If your voltage is varying like that, its probably your Voltage Regulator. You can have the alternator rebuilt and the regulator itself probably costs like $20.
Gene, your voltage looks ok, it should drop a little below 13V at idle, and during normal driving when its cold the voltage should be at ~14.5 (you cant trust the in-dash voltmeter) when it gets warmed up good, it should be around 13.5V. I dont think you really have a problem, but you can take the alternator off and have it tested at Autozone or wherever, its not hard to take them off.
Gene, your voltage looks ok, it should drop a little below 13V at idle, and during normal driving when its cold the voltage should be at ~14.5 (you cant trust the in-dash voltmeter) when it gets warmed up good, it should be around 13.5V. I dont think you really have a problem, but you can take the alternator off and have it tested at Autozone or wherever, its not hard to take them off.
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From: Punta Gorda, FL
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Re: voltage wanders a little...is this normal? (vader86)
When it dropped down to 12.2 volts (which to me seems like there was no alt. output, or very little) the damn blinker wouldnt blink right. it would stay on for 5 seconds, then turn off for 5. VERY slow. Is it difficult to change the regulator? Is that inside the alternator?
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Re: voltage wanders a little...is this normal? (vetteweiser)
Gene, yours doesnt sound like a regulator problem, if there is a problem. But yes, the regulator is inside the alternator.
The 12.2 is low, but you cant trust the in-dash voltmeter either. Mine is off by .6V. I suggest you take the alternator off and have it tested for the correct ampage output.
The 12.2 is low, but you cant trust the in-dash voltmeter either. Mine is off by .6V. I suggest you take the alternator off and have it tested for the correct ampage output.
Team Owner
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From: Cincinnati, Oh USA
Re: voltage wanders a little...is this normal? (LT4Coupe)
Unless you have a flickering load (unlikely) you should not see flickering voltage. The voltage regulator can oscillate and it shouldn't. When the engine is at idle speed, the alternator is not turning fast enough to produce rated current and under a heavy electrical load the voltage will drop because the voltage regulator is at its limit (it regulates by controlling the field current) and the battery will be delivering current to the electrical system. Its nothing to worry about because you don't spend much time (percentage wise) idling and the alternator will pick up the load and charge the battery when you get underway.
