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Trying to figure out what's responsible for:

Whenever I increase the electric load (press a power window button, turn on headlights, etc..) the power drops instantaneously then comes up again: The dashboard lights will dim for 1 sec, tape/radio/speakers will stop+start and also the RPMs will drop a bit and come up again.

The following two are *very rare*, and I can't remember if at the time I caused them by doing something that increased the electric load:
* I've seen the speedometer jump to 130mph then back
* The RPMs drop instantaneously to the point that the engine stops (e.g. while waiting at a traffic light)

In all the cases the symptoms are instantaneous, then things get back to normal.

 
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sounds like faulty altenator,,,, watcht the volts or amps with a dmm or amp probe,,,

 
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sounds normal. with a mini charging system and barely 60 amps to run all the car systems, any extra power draw items (a/c, windows, lights, wipers, blower, etc) will cause what you are describing because you are switching from 14v alternator to 12v battery voltage. now as for the car shutting off, that is likely due to some other issue like a dirty idle air valve that is unable to raise idle after it dips down. if you had the old style 01-02 lx/ex or 01-05 dx/vp clusters, those had some hiccups that caused the needles to randomly jump around for no reason.

 
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it's a 98 lx and I cleaned the air valve 1 month ago because of rpm surge. Other than that car's idle is pretty normal.
Btw, everything is stock.

Hmm I don't remember the tape stopping and starting again and the speakers instantaneously muting every time I pressed the power window button (without headlights or anything else on). In the night the headlights instantaneously dim to about 20% (almost off) and come back again when I use power windows in the highway.

Also, I noticed that when I'm waiting at a traffic signal with headlights on and my foot on the break pedal and I press the power window button the RPMs drop to such an extent that the engine almost halts for a second.

Last, turning off the engine causes the tape to stop for 2 seconds and come back again.

Will check the voltage at the battery under some of these conditions to see if it fluctuates more than it should.

 
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ah yeah, forgot to mention that the symptoms are more visible when I haven't "played" with the electric parts for some time.
In other words: if i press the button a second time it's not going to be that bad... i'll have to wait a bit (few minutes) then do it again in order to reproduce the problem

 
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ok a little bit more info:
I noticed that e.g. when I release the power window button the lights become too bright instantly then stabilize. So as far as I understand it doesn't seem to be a power issue but rather a regulation issue. What part regulates the voltage/amperage based on demand? That circuit seems to have some delay

 
Rep Power: 811

sounds like you need to install a voltmeter in the car and watch what happens to voltage as you do these things. i think every car needs one for daily driving and also diagnostics. if your voltage is rising above 14.5v while the car is warmed up, there is a problem with the alternator voltage regulator.

 
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I have a voltmeter at home and I'll check it when I get back tonight. Should I check the voltage on the battery terminals?

 
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yeah, any hot wire on the car should tell you. you prolly need to connect it to the 12v socket plug in the car to see what happens. may be difficult doing it under the hood and playing with the accessories.