Lights Dim with the gas

M

my66coupe

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Apr 30, 2002

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Arizona fountain hills

Feb 5, 2004

#1

• Feb 5, 2004

• #1

Ok I have this cheapo battery that I have used regularly, and when I rev it in park, the headlights stay the same. I now have this used optima in my car, and when I rev it in park the lights will go bright and when I let off, they will get lighter. I have a new alternator in the car also. What gives?

Mike

 

SuperDave

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Feb 5, 2004

#2

• Feb 5, 2004

• #2

my66coupe said:

Ok I have this cheapo battery that I have used regularly, and when I rev it in park, the headlights stay the same. I now have this used optima in my car, and when I rev it in park the lights will go bright and when I let off, they will get lighter. I have a new alternator in the car also. What gives?

Mike

Click to expand...

Regulator problem

 

M

my66coupe

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#3

• Feb 5, 2004

• #3

brand new regulator also, why would this do it with one battery and not with the other? I thought that this was more battery related?

Mike

 

SuperDave

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#4

• Feb 5, 2004

• #4

Your comment puzzles me. You state that the light go "brighter" when you step on the gas then they go "lighter" when you let off. What do you mean, Eh?

 

M

my66coupe

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#5

• Feb 5, 2004

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Sorry I found that hard to word, they go brighter when I rev it up, and when I get off the gas, the lights dim down, lower, "lighter".

Mike

 

2nd Mustang

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Feb 5, 2004

#6

• Feb 5, 2004

• #6

What kind of lights, and how many amp output of the alternator. My Stang does the same thing with a stock alternator and newer halogen type lights. Many articles have been written on this subject in magazines. I think mine is the alternator not being able to handle the load when the lights are turned on. My voltmeter shows 14 volts with motor at idle, but dips down to 13 when I turn on the headlights. Reving up the idle brings the voltage back to 14 with the headlights on.

 

SuperDave

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Feb 6, 2004

#7

• Feb 6, 2004

• #7

My former '65 Continental did the same thing until I installed an ELECTRONIC regulator. (The car had halogens)

 

RGS0907

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Aug 21, 2003

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Feb 6, 2004

#8

• Feb 6, 2004

• #8

my66coupe said:

Sorry I found that hard to word, they go brighter when I rev it up, and when I get off the gas, the lights dim down, lower, "lighter".

Mike

Click to expand...

It still sounds like the regulator. But you can check the battery with a hydrometer and a volt meter to see if any of the cells are dead or shorted out. Also, sometimes the starter will short out & put a constant drain on the battery.

 

68GEETEE

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Nov 21, 2003

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Feb 7, 2004

#9

• Feb 7, 2004

• #9

I would think the plug that goes to your voltage regulator could be dirty from years of oxidation. Get a spray can of electrical contact cleaner and spray the metal tabs inside your wiring plug, then see how it does. If that doesnt work, then I am thinking your headlight switch is on its way out.


stupid me forgot to mention that the fan belt that drives your alternator may be loose, check it for play.