Charging issue when warm

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Fastonthetrack

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Nov 23, 2011

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#1

• Nov 23, 2011

• #1

Im having a charging problem once the car is warm.. I have the 3G upgrade, brand new alternator and battery as of yesterday and once the car gets warm it stops charging completely. Everything works fine when cold.. after 15-20 minutes of driving the volt gauge starts bouncing around then she stops charging.. all the wiring between the alt, battery, ground and solenoid is good.. Any suggestions would be great.. Thanks

 

Three50won

10 Year Member

Jul 11, 2010

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Nov 23, 2011

#2

• Nov 23, 2011

• #2

Fastonthetrack...are there any other signs that it's not charging (besides the gauge)? Is the battery light coming on? Any lights dimming? I'd say drive it for 20 minutes and then have the charging system checked at a shop. Or maybe you got a bum alternator. That's happened to myself and a few friends of mine once before...

 

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Fastonthetrack

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#3

• Nov 23, 2011

• #3

Once warm and the Alt stops charging, we tested it and it says Voltage regulator low voltage. Tried 2 new alternators this week and same problem. Yes lights dim, no battery light on dash though. it will charge intermittently then completely stop.. Ill let her sit about an hour or so then it will charge fine...

 

Blown88GT

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Nov 13, 1999

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Nov 23, 2011

#4

• Nov 23, 2011

• #4

Where did you get the 3G? A lot of the parts store stuff is junk.

 

F

Fastonthetrack

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Nov 23, 2011

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#5

• Nov 23, 2011

• #5

Its an autozone repro, but its the 3rd one, same problem on 3 alternators? s

 

Blown88GT

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Nov 23, 2011

#6

• Nov 23, 2011

• #6

I went through 2 Autozone distributors in less than a week. All remans by Cardone, they test nothing, just throw new parts on it & ship it. There is no QC inspection or they would have caught the 2nd dizzy in about 1 minute through visual inspection only. My buddy spotted it in 5 sec.

Get your money refunded, look for one in a junkyard & have it rebuilt by your local alternator shop.

 

jrichker

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Nov 23, 2011

#7

• Nov 23, 2011

• #7

The reman alternators are highly suspect.

Some grounding information that often gets overlooked...

2.) The secondary power ground is between the back of the intake manifold and the driver's side firewall. It is often missing or loose. It supplies ground for the alternator, A/C compressor clutch and other electrical accessories such as the gauges.

Any car that has a 3G or high output current alternator needs a 4 gauge ground wire running from the block to the chassis ground where the battery pigtail ground connects. The 3G has a 130 amp capacity, so you wire the power side with 4 gauge wire. It stands to reason that the ground side handles just as much current, so it needs to be 4 gauge too.

The picture shows the common ground point for the battery , computer, & extra 3G alternator ground wire as described above in paragraph 2. A screwdriver points to the bolt that is the common ground point.

The battery common ground is a 10 gauge pigtail with the computer ground attached to it.
Picture courtesy timewarped1972


Correct negative battery ground cable.

 

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F

Fastonthetrack

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Nov 30, 2011

#8

• Nov 30, 2011

• #8

It was the car alarm!

 

Blown88GT

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Nov 30, 2011

#9

• Nov 30, 2011

• #9

Fastonthetrack said:

It was the car alarm!

Click to expand...

What does that have to do with alternator functioning properly?

 

F

Fastonthetrack

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#10

• Nov 30, 2011

• #10

The alarm was spliced between the alt and the ignition...

 

jrichker

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#11

• Dec 1, 2011

• #11

Another victim of the previous owner's efforts. More people can mess up electrical wiring and installation than any other single item on cars. It is simple if you know how electricity works and how to do it right.