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Lights fluttering

  • Thread starter Thread starter streetstang67
  • Start date Start date May 28, 2005

streetstang67

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Mar 5, 2003
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Lexington, SC
May 28, 2005
#1
  • May 28, 2005
  • #1
I've been through a lot of charging issues, and probably still have some, but they are 'out of sight and out of mind' for now. Anyway, a problem I've had for a while is my headlights and guage lights flashing or fluttering...going from bright to dim varying with engine speed. What can I do to fix this? BTW, I've already replaced the alternator and voltage regulator.
 

Platonic Solid

Founding Member
May 29, 2002
1,960
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39
CT-USA
May 28, 2005
#2
  • May 28, 2005
  • #2
Regardless of the fact that you have a new alternator, it still sounds like an alternator problem to me (bad diode). Are you running standard headlamps or higher draw halogens?
.
 

streetstang67

Member
Mar 5, 2003
573
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Lexington, SC
May 28, 2005
#3
  • May 28, 2005
  • #3
Standard headlamps and stadard alternator.
 
R

ravenblack67

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Apr 2, 2005
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May 28, 2005
#4
  • May 28, 2005
  • #4
Normally, I would say replace the regulator. If you already did that, check for a bad ground
 

streetstang67

Member
Mar 5, 2003
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Lexington, SC
May 28, 2005
#5
  • May 28, 2005
  • #5
ravenblack67 said:
check for a bad ground
Click to expand...

Where?
 
6

68modstang

New Member
May 7, 2004
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0
Monrovia, CA
May 28, 2005
#6
  • May 28, 2005
  • #6
Just fixed this problem on my 68. Thought it was the alternator, ended up being cheaper- try buying a new voltage regulator. If your keeping it original it'll cost you about $35, otherwise your local autozone, etc. should have an aftermarket for about $15.00. By the way, always a good time to check the grounding cable on the engine.
 

streetstang67

Member
Mar 5, 2003
573
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Lexington, SC
May 29, 2005
#7
  • May 29, 2005
  • #7
Well how could I diagnose this problem? I assume the first step would be to determine the charging volts/amps. What else? What should the amperage and voltage be, and where should I test it?
 

Dark Knight

Founding Member
Feb 1, 2000
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Chandler, Az.
May 29, 2005
#8
  • May 29, 2005
  • #8
most parts stores will test the alternator and battery while they're in the car.. might have them do it..

the one ground problems I see the most is the one from the engine to the firewall... usually goes under one of the rear intake bolts and to the firewall..
 

HistoricMustang

Active Member
Apr 11, 2003
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46
Confederate States of America
May 30, 2005
#9
  • May 30, 2005
  • #9
streetstang67 said:
I've been through a lot of charging issues, and probably still have some, but they are 'out of sight and out of mind' for now. Anyway, a problem I've had for a while is my headlights and guage lights flashing or fluttering...going from bright to dim varying with engine speed. What can I do to fix this? BTW, I've already replaced the alternator and voltage regulator.
Click to expand...

Could very well be something as simple as your light switch. Go ahead and replace it if still the original. Fairly inexpensive and somewhat simple job.

Happy Motoring,

HistoricMustang
www.historicmustang.com
 

streetstang67

Member
Mar 5, 2003
573
0
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Lexington, SC
May 30, 2005
#10
  • May 30, 2005
  • #10
I wish I hadn't replaced it, then I'd have something to look forward to. No, I've already replaced it when my dash lights quit.
 

Platonic Solid

Founding Member
May 29, 2002
1,960
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39
CT-USA
May 30, 2005
#11
  • May 30, 2005
  • #11
streetstang67 said:
I wish I hadn't replaced it, then I'd have something to look forward to. No, I've already replaced it when my dash lights quit.
Click to expand...
LOL, Well then there's nothing left except wiring (unless you replaced that too.) and connections.
.
 
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