Intermittent Voltage Drop
Intermittent Voltage Drop Most of the alternator threads I read were in the Gen III External Engine section, but maybe I'll have more luck in here?
https://ls1tech.com/forums/generatio...tage-drop.html
https://ls1tech.com/forums/generatio...tage-drop.html
I have checked the DS one that connects the block to the DS sub frame - it runs along the alternator signal wire, I have checked the main one off of the battery to the PS fender, the junction block one on the DS fender, and the main ground to the block on the PS. Any other you can think of?
have you checked the power wire that plugs into the alternator? mine looked like someone had pulled it without pushing in the clip on the plug. it was only getting power from 3 or 4 strands of copper wire.
Main power wire or signal wire? I believe I said I checked both, replaced the power wire from the alternator to the battery with 4 gauge and replaced 6-8 inches of the 24 gauge signal wire with 18 gauge power wire.
First i'll start by saying my stock alternator took a dive a month or so ago, and I replaced it with a truck alternator. It worked fine for a day or so then began intermittently cutting out, and finally not charging the battery. Ends up I hadn't tightened the outbound power wire well enough to the alternator, and works like a charm now - so I understand your frustration hehe.
It sounds to me like you have a weak, intermittent electrical connection and not a bad alternator. Start over by ensuring electrical connectivity going from the + battery terminal through the loop to the alternator and back to the - battery terminal. I would check the cable bolting into the - battery terminal, the cable bolting into the + battery terminal, and the power cable going to the alternator and possibly the signal/exciter wire at the alternator. After you've checked those few connections, then bring the alternator to autozone/o'reilly and have then do a test on it. If this all does check out, I think you have no choice but to begin tracing the wires.
The alternator should only need two wires - signal/exciter wire and power wire. My KG3 only had two.
I see you went through the hassle to enlarge some of the wires while you were in there. This splicing may end up causing you headaches as opposed to relaying a larger continuous wire
It sounds to me like you have a weak, intermittent electrical connection and not a bad alternator. Start over by ensuring electrical connectivity going from the + battery terminal through the loop to the alternator and back to the - battery terminal. I would check the cable bolting into the - battery terminal, the cable bolting into the + battery terminal, and the power cable going to the alternator and possibly the signal/exciter wire at the alternator. After you've checked those few connections, then bring the alternator to autozone/o'reilly and have then do a test on it. If this all does check out, I think you have no choice but to begin tracing the wires.
The alternator should only need two wires - signal/exciter wire and power wire. My KG3 only had two.
I see you went through the hassle to enlarge some of the wires while you were in there. This splicing may end up causing you headaches as opposed to relaying a larger continuous wire
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First i'll start by saying my stock alternator took a dive a month or so ago, and I replaced it with a truck alternator. It worked fine for a day or so then began intermittently cutting out, and finally not charging the battery. Ends up I hadn't tightened the outbound power wire well enough to the alternator, and works like a charm now - so I understand your frustration hehe.
It sounds to me like you have a weak, intermittent electrical connection and not a bad alternator. Start over by ensuring electrical connectivity going from the + battery terminal through the loop to the alternator and back to the - battery terminal. I would check the cable bolting into the - battery terminal, the cable bolting into the + battery terminal, and the power cable going to the alternator and possibly the signal/exciter wire at the alternator. After you've checked those few connections, then bring the alternator to autozone/o'reilly and have then do a test on it. If this all does check out, I think you have no choice but to begin tracing the wires.
The alternator should only need two wires - signal/exciter wire and power wire. My KG3 only had two.
I see you went through the hassle to enlarge some of the wires while you were in there. This splicing may end up causing you headaches as opposed to relaying a larger continuous wire
It sounds to me like you have a weak, intermittent electrical connection and not a bad alternator. Start over by ensuring electrical connectivity going from the + battery terminal through the loop to the alternator and back to the - battery terminal. I would check the cable bolting into the - battery terminal, the cable bolting into the + battery terminal, and the power cable going to the alternator and possibly the signal/exciter wire at the alternator. After you've checked those few connections, then bring the alternator to autozone/o'reilly and have then do a test on it. If this all does check out, I think you have no choice but to begin tracing the wires.
The alternator should only need two wires - signal/exciter wire and power wire. My KG3 only had two.
I see you went through the hassle to enlarge some of the wires while you were in there. This splicing may end up causing you headaches as opposed to relaying a larger continuous wire
I may have the alternator tested tonight if they're not busy at the local parts stores. Thanks for your help thus far! It may be a while with me responding with results as I work late and usually only find time to work on the car on the weekends.
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Verdad Gallardo Ok, I didn't get to do anything last night because I didn't get home until 8 ish.
I want to put this into diagnostic generalizations. So, if my voltage experiences an intermittent drop, one of the following must be happening.
1. The PCM is not signaling the alternator to engage.
2. The alternator's rectifier is failing.
3. The alternator is failing.
4. There are faulty closed circuit connections.
5. A high load is momentarily placed on the system.
----A. Corrosion/Junk floating in the battery causing a temporary short.
----B. A Failing electrical component, ie when a fuel pump may be on it's way out, they may momentarily or constantly draw high amperage.
I'm not saying all of these are practical, but just trying to list all general conditions that could/would present themselves in the manner I am experiencing. I know some higher rated fuses may not fail the instant the current exceeds their rating, again generalizations, and if momentary, could go without burning itself up. This is unlikely, but possible. I guess after I get the alternator tested and check those ground connections as I was supposed to, I may start removing some circuits from the system attempting to single out the faulty circuit before shredding my wiring harness open to replace the alternator signal wire.
Thoughts? Additions to the list?
I want to put this into diagnostic generalizations. So, if my voltage experiences an intermittent drop, one of the following must be happening.
1. The PCM is not signaling the alternator to engage.
2. The alternator's rectifier is failing.
3. The alternator is failing.
4. There are faulty closed circuit connections.
5. A high load is momentarily placed on the system.
----A. Corrosion/Junk floating in the battery causing a temporary short.
----B. A Failing electrical component, ie when a fuel pump may be on it's way out, they may momentarily or constantly draw high amperage.
I'm not saying all of these are practical, but just trying to list all general conditions that could/would present themselves in the manner I am experiencing. I know some higher rated fuses may not fail the instant the current exceeds their rating, again generalizations, and if momentary, could go without burning itself up. This is unlikely, but possible. I guess after I get the alternator tested and check those ground connections as I was supposed to, I may start removing some circuits from the system attempting to single out the faulty circuit before shredding my wiring harness open to replace the alternator signal wire.
Thoughts? Additions to the list?
Unless I am mistaken, the PCM on our cars doesn't affect the alternator. The alternator action is simply reacting to the voltage difference between the alternator and battery via signal wire. Someone double check me on this please
