Lights fluttering

[streetstang67]

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]

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?
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[streetstang67]

Standard headlamps and stadard alternator.

 

[ravenblack67]

Normally, I would say replace the regulator. If you already did that, check for a bad ground

 

[streetstang67]

check for a bad ground

Where?

 

[68modstang]

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]

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]

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]

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.

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]

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]

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.

LOL, Well then there's nothing left except wiring (unless you replaced that too.) and connections.
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