New Alternator Has problems Charging at Idle Options

[barterj]

Tonight while driving around boston, my battery light started to go on and off. I was like great, my alternator that i just got a week ago is a dud. BUT, the battery light was coming on when the engine rpms was over about 3.5k, ALSO the lights would get really bright, all the lights. My father told me he thinks its the voltage regulator from what i told him, which is in the alternator. Anyone have any ideas, looking for any second opinions and or agreement with what my father told me, thanks.

This post has been edited by barterj: Feb 17, 2011 - 6:32 PM

[Spider77]

my suggestion, take a reading, while at idle and then while at x amount of revs....should get around 14.some across the board

[barterj]

Thats what my repair manual says too, but both alternators i've gotten from autozone have never charged at 14.something at idle. guess i'ts off to testing my car, even though the alternator will most likely pass autozones tester

[Spider77]

both alt's? So you've been through what, 3 of them so far (one stock, two from autozone)? Cause I gotta say, if you've put more than 1 alt, and your probs are the same, then it has to be something else. How is your belt tension?

[barterj]

Belt tension is good, I tested it today and it's spiking to 16-18 volts. I'm going to have it tested tomorrow and see what they say. Does the computer control the voltage regulator in our cars? I was thinking that if it doea, maybe my computer is bad and that is whats cause my car to eat alternators. This is also only happening when the alternator gets hot. When is cold its fine, it even charges right, the last one was the same way, when i was cold it charged but after about 10 minutes it wouldn't charge at idle which is also when i was very hot to the touch. The last one just died completely where as the one i have now spikes in voltage so the problems are different.

This post has been edited by barterj: Oct 22, 2010 - 7:31 PM

[Hanyo]

take your car to auto zone and have them load test your system.

Sound like a bad battery cable or a bad ground.

If your alternator gets hot, so should your battery.

What it sounds like to me is your cars cables or ground is bad and all the electricity its making is getting dissipated and turned into heat.

Our cars do not use a computer controlled alternator. Everything is self contained in the alternator.

[barterj]

This weekend i'm going to replace all the ground wires as the main one to the battery looks to be corroded at both ends, won't bother to check continuity because if one strand is not broken then the wire will show continuity. The battery is good, i know that much and now that i know that the voltage regular is not controlled by the computer, i can start on actually figuring out the problem.

[barterj]

So i replaced 2 ground wires, hoping that's all there are and had the alternator replaced under warranty. However, i'm still getting a low charge at idle. Every time i have the charging system tested the test results say low reg. which i assume is low regulator/regulation of voltage. All the fuses are fine and as far as i can tell there are no shorts in my car, if there was a short i would have blown fuses which i don't. So...any ideas? Or should i just find an oem alternator at the scrap yard. Thanks

[chacha]

do the alt test....start your car and then pull off the positive terminal from battery with car still running...if your car dies...then it's your alt....if it is still running...then it's your battery.

[barterj]

Sorry to pull this from the depths of who knows where, but I know I shouldn't make a bunch of threads on the same issue.

I am still having problems with my alternator charging. I have replaced it since I last got advice to what could be wrong, so no more voltage spikes to 18 volts , but now the newer one doesn't want to charge at idle. All connections are clean, belt tension is correct according to Haynes Repair Manual, new battery and negative lead(complete wire that connect battery to ground on the transmission and body above driver low beam), all fuses have been checked and none are blown.

Symptoms:
Idle(~800rpm) with a load; Headlight, heater on full and rear defrost on:
- Voltage output is 12.5-13 volts

Idle without a load; all accessories off
- Voltage Output is 14.5-14.7 volts

1100 rpms or greater with same load as stated above:
- Voltage output is 13.7-14.7 volts

1100rpms or greater without a load:
- 14.5-14.8 volts

Idk what to make of this, but its starting to really confuse me and make me think more and more that there is something very wrong with my car, but I'm not blowing fuses, so I think its safe to assume there is nothing wrong in the wiring.

This post has been edited by barterj: Feb 17, 2011 - 6:34 PM

[barterj]

Video of my issue:

http://www.youtube.com/watch?v=ejfKgmgH08s

[chacha]

change your alt...borrow a alt from a camry...not the new cam but one with a 5sfe...test it out....take the battery to the shop to recharge and test if bat is bad...go to a kragen or o'reily if you got one. autozone people are not too bright from my experience.

worse comes to worse...it's gotta be one of those two culprit if your charge doesn't hold. buy battery and return it if it doesn't work...likewise with the alternator if fuse not blown.

This post has been edited by chacha: Feb 18, 2011 - 12:32 AM

[barterj]

Thanks, i think its just an issue with how autozone is rebuilding the alternators, there is a celica in the scrap yard near my house that i'm going to go test when i go home in a couple weeks.
I sure its not the battery, thats new as of october.

[st202gt]

best is u must try different place to test if your alt is bad.. most of the time remanfac alternator tend to have built poor. best u will to purchase a brand new from dealer or try to burrow someone that have same car or engine.

[Driveby]

Sorry to pull this from the depths of who knows where, but I know I shouldn't make a bunch of threads on the same issue.

I am still having problems with my alternator charging. I have replaced it since I last got advice to what could be wrong, so no more voltage spikes to 18 volts , but now the newer one doesn't want to charge at idle. All connections are clean, belt tension is correct according to Haynes Repair Manual, new battery and negative lead(complete wire that connect battery to ground on the transmission and body above driver low beam), all fuses have been checked and none are blown.

Symptoms:
Idle(~800rpm) with a load; Headlight, heater on full and rear defrost on:
- Voltage output is 12.5-13 volts

Idle without a load; all accessories off
- Voltage Output is 14.5-14.7 volts

1100 rpms or greater with same load as stated above:
- Voltage output is 13.7-14.7 volts

1100rpms or greater without a load:
- 14.5-14.8 volts

Idk what to make of this, but its starting to really confuse me and make me think more and more that there is something very wrong with my car, but I'm not blowing fuses, so I think its safe to assume there is nothing wrong in the wiring.

Your alternator readings are ok, is your battery going flat or are you trying (hoping) to get different readings on your meter?

[barterj]

Sorry to pull this from the depths of who knows where, but I know I shouldn't make a bunch of threads on the same issue.

I am still having problems with my alternator charging. I have replaced it since I last got advice to what could be wrong, so no more voltage spikes to 18 volts , but now the newer one doesn't want to charge at idle. All connections are clean, belt tension is correct according to Haynes Repair Manual, new battery and negative lead(complete wire that connect battery to ground on the transmission and body above driver low beam), all fuses have been checked and none are blown.

Symptoms:
Idle(~800rpm) with a load; Headlight, heater on full and rear defrost on:
- Voltage output is 12.5-13 volts

Idle without a load; all accessories off
- Voltage Output is 14.5-14.7 volts

1100 rpms or greater with same load as stated above:
- Voltage output is 13.7-14.7 volts

1100rpms or greater without a load:
- 14.5-14.8 volts

Idk what to make of this, but its starting to really confuse me and make me think more and more that there is something very wrong with my car, but I'm not blowing fuses, so I think its safe to assume there is nothing wrong in the wiring.

Your alternator readings are ok, is your battery going flat or are you trying (hoping) to get different readings on your meter?

The idle reading with a load isn't okay, when I'm at a stop light all of my lights dim, including headlights, even the book states it should be significantly higher output than that at idle, 13.5-15.1 volts, it states that the voltage should drop, but then return to that 13.15.1 volt range.

I'm planning on getting a factory alternator and i'm going to attempt to get my money back for this one because non of the 4 I've had from Autozone have worked right

Just wondering, has anyone else ever had an issue like this?

[chacha]

yeah...it is a hit or miss with me too...i got my 160amp alt from ebay...worked great....he rebuilds and put in stronger amp coil inside

high output

This post has been edited by chacha: Feb 19, 2011 - 11:35 AM

[lagos]

I get my alternators from autozone. Sometimes the rebuilds are hit or miss, but with the lifetime warranty, you can always take it back if it ever fails.

Also when buying your alternator, make sure to buy the 80amp automatic trans alternator, vs the 70amp manual trans version. They are the same price and the extra 10 amps makes a huge difference.

[barterj]

I get my alternators from autozone. Sometimes the rebuilds are hit or miss, but with the lifetime warranty, you can always take it back if it ever fails.

Also when buying your alternator, make sure to buy the 80amp automatic trans alternator, vs the 70amp manual trans version. They are the same price and the extra 10 amps makes a huge difference.

Yeah, all the ones i've had have been crap, but i have a friend that works a toyota dealership as a mechanic and he told me he can get me one for 170

About the 80amp, autozone won't let me get that one because they said it voids the warranty somehow, i could understand putting a lower amp alternator in my car voiding the warranty, but a stronger one...who knows

I'm gonna try one more from autozone, and it doesn't work i'm going back to a factory alt.

[barterj]

chacha, how long have you had yours?

i blew my original when my cap. went bad on my subs and i know i should have had a high output then but kept putting it off, and now i'm regretting that decision.

so, i take it everyone who's said something so far agrees there's nothing wrong with my car, just bad luck with reman. alternators?

This post has been edited by barterj: Feb 19, 2011 - 7:50 PM