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Discussion Starter #1
Anybody have an idea what might cause this voltage drop? Drops really low when lights are on, but only at idle. As soon as I hit the gas it goes right back up. I thought maybe it was my old negative battery cable, but a new one didn’t fix it. Thanks in advance.
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Nope that's pretty much all fox's. When I upgraded to a bigger alternator I thought that would go away too but nope still did it. It wasn't till I went to l.e.d headlights is when I noticed it stopped doing that.
 

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Ya know, I’ve seen a lot of people saying that across the internet, figured I’d ask here since I’ve found a lot of great advice on the corral. It hasn’t given me any trouble, charging or otherwise, just doesn’t seem right. Looks like maybe a bigger alt is just what the doctor ordered though. And nice to see the headlights improved it too, since they are already on my list. What kind do you have? And do you like them? Beam pattern, brightness, etc...
 

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you can overdrive the alt, ie

smaller alt pulley or larger crank or both

put your blower on high at the same time, and watch it drop even faster further
 

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This could be a number of things. Bad chassis connection, dirty switch contacts, bad voltage regulator, etc. I do give the electrical engineer at Ford some credit, as these voltage drops don't really seem to affect the car all that much. Outside of the seeing things go dim/bright while using the blinker or the fan speed changing if the light go on/off.
 

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Discussion Starter #6
Well, I can live with that. Maybe I’ll just upgrade the headlights to led and get a bigger alternator and call it good.
 

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Ya know, I’ve seen a lot of people saying that across the internet, figured I’d ask here since I’ve found a lot of great advice on the corral. It hasn’t given me any trouble, charging or otherwise, just doesn’t seem right. Looks like maybe a bigger alt is just what the doctor ordered though. And nice to see the headlights improved it too, since they are already on my list. What kind do you have? And do you like them? Beam pattern, brightness, etc...
They're actually a cheap brand from Amazon called hikira there 40 bucks for the set they have other brands just Google 9004 led headlight bulb. These work great with no problems I've had them over a year now and dam it's a major improvement over the stock one's. The bean pattern is like the factory ones just brighter.
 

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Discussion Starter #8
Nice, I’ll have a look. I bought some eBay ones for my truck that are great, but they don’t make a 9004. Looks like I’ll be making Jeff Bezos a little bit richer 🤷🏼‍♂️
 

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When you see the issue, check the voltage at the battery. Maybe just a gauge issue, not a charging issue.
 

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Discussion Starter #10
When you see the issue, check the voltage at the battery. Maybe just a gauge issue, not a charging issue.
Good call, possibly rule out a bunch of gremlins. The nice thing is I can replicate the issue on demand so should be a quick check.
 
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