Battery/Alt. Idiot light problems?

[Josh89accord]

Hey guys, once I figure it all out, one more thing pops up... Whenever my car is idling, my battery idiot light is on on the dash, but whenever i rev it, it goes off, but then goes on as soon as i let off the throttle. Any ideas? Checked all my grounds in the engine bay, and all are secure.

Thanks in advance!
Josh

[russiankid]

Alternator is going out.

[DBMaster]

2nd russiankid. I don't know why cars have a graphic of the battery on that stupid light. It never indicates a bad battery, just problems with the charging system. Older cars used to have "ALT" on the light.

[Josh89accord]

Alternator is brand new... I've got a year warrenty on it. So thats the only possible thing? Thanks guys!

[YK86]

It sounds like the brushes or maybe even the voltage regulator is bad but both should be fine in a new/reman alt. I'd take it back under warranty.

[russiankid]

Where did you get your alt from? If you got it from Advance Auto or Autozone, I am not surprised its bad.

[lostforawhile]

make sure your belt is tight, that can be caused by a loose belt. if it's from autozone or advance it's a cheap chinese rebuild. I have never gotten anything good electrical from them. warranty is no good if you have to take the stupid thing out. I ended up with one from nappa. long story, but I have a brand new one here I haven't installed yet,If i have time i might sell you the one off the car if needed,it's not that old and it works fine. also a nappa one. I was going to polish the one thats not on the car yet.

[bank2me]

My bros maxima recently had that problem with an alternator from autozone. We had put a new one from autozone on back in march and about a month ago the light came on, then revved it above 1500 rpm light shuts off. Then the thing was ok for a few weeks, light came back on 2 weeks ago. Let my bro take my jump pack to work, sure enough alternator goes out. Took it to autozone they said the bearing was goin out. Sounds like alteernator.

[Josh89accord]

I got it from an ebay store, it was a reman'ed 135 watts or so? one guy on here bought one so I went ahead and bought one, its a damn good alt. It might just be my belt though, cuz sometimes on cold mornings, it squeeks. Thanks for the quick replys guys. 3geez is an amazing forum for these cars.

[russiankid]

Get a digital volt meter and see what the output is at the battery terminals on idle.

[lostforawhile]

you also need something to measure output, it could read 14 volts,but the regulator is bad and only allowing 10 amps or so output. just an example. regulator controls the field current,which determines how many amps it's producing at a given time. if you put a load on it,and the current doesn't increase, then it's the regulator. try turning on everything electrical in the car,lights, ac, etc, then see if the voltage drops out with the car running.

[MessyHonda]

my alternator went bad after like 2 months use and it was a napa one...i exchanged it and now it has no problems...alternators tend to fail

[lostforawhile]

my alternator went bad after like 2 months use and it was a napa one...i exchanged it and now it has no problems...alternators tend to failthe main problem is the alternator being close to the ground,and 90 percent of these cars missing the splash shield. the other is the regulator,before i replace this one i'm going to try and find a factory regulator for it. also they have an inherent problem with the regulators overheating, these were some of the first small alternators to produce as much current as the much larger delco type. so the bugs hadn't all been worked out yet.

[Dr_Snooz]

the main problem is the alternator being close to the ground,and 90 percent of these cars missing the splash shield. the other is the regulator,before i replace this one i'm going to try and find a factory regulator for it. also they have an inherent problem with the regulators overheating, these were some of the first small alternators to produce as much current as the much larger delco type. so the bugs hadn't all been worked out yet.

Any thoughts on keeping it cool? My Bimmer has a special duct in the bumper to guide air across the alt. Any way of rigging something similar for ours?

[lostforawhile]

Any thoughts on keeping it cool? My Bimmer has a special duct in the bumper to guide air across the alt. Any way of rigging something similar for ours?
i've thought of that am working on it,just don't want to duct water to it

[Josh89accord]

Ok guys, contacted the guy I bought the alternator off of on ebay ( i.d. more_amps) and hes sending me a new one, sounds like the guy is a straight up guy. I would recommend buying one from him if your in for a new more powerful alt than stock.

[russiankid]

Any thoughts on keeping it cool? My Bimmer has a special duct in the bumper to guide air across the alt. Any way of rigging something similar for ours?

My 525i has tubing going straight to the alt. The fans of the alt suck in air through the tube.:rockon:

[lostforawhile]

how do you know this alternator is more powerful then stock? he says 135 watts that's only 10 amps at 13.5 volts. the factory alternator is around 60 amps i believe. if you were running an ad on ebay you could advertise WOW! 86-89 ALTERNATOR 810 WATTS!! HIGH POWER! BUT IN REALITY THAT'S A FACTORY STOCK ALTERNATOR

[Josh89accord]

Well, all I know is that on my old alternator, the lights would dim when the bass came on from my subs, and now theirs no light dimming.

[lostforawhile]

Well, all I know is that on my old alternator, the lights would dim when the bass came on from my subs, and now theirs no light dimming.might have been because the old alternator was going bad and could no longer produce it's rated output.

[Josh89accord]

might have been because the old alternator was going bad and could no longer produce it's rated output.

That could be very well possible, I mean i don't know if they actually did beef up the internals or what, but it seems as if it works better. I'm just glad his one year warranty is up to par.

[bank2me]

Good luck Josh good to hear you're gettin a new alternator free. Keep that 3gee on the road buddy:cheers:.

[LUX88LXI]

the other thing about BMW alternators is that you can actually get to them LOL... I have to change the alt. in my 3g the reman autolite from kragen took a shit after 20k miles... Im a little angry that the axle needs to be removed to change the alt, ridiculous.

[lostforawhile]

the other thing about BMW alternators is that you can actually get to them LOL... I have to change the alt. in my 3g the reman autolite from kragen took a shit after 20k miles... Im a little angry that the axle needs to be removed to change the alt, ridiculous.only on the carb cars,you can take it out much eaisier on the FI cars. I found out you have to drop the axle to get the one out on my wifes 98 civic also. SO it's probably like that on lots of Hondas

[bank2me]

Yea I took off my alternator without takin out the axle.

[lostforawhile]

I really thought about moving it to the cradle for the AC compressor, but the same belt drives the water pump

[Civic Accord Honda]

Yea I took off my alternator without takin out the axle.
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