my alt is going?

[1-3-2-4]

This is the 2nd time it's happened in under two weeks.. and each time by the time it stops and i check the output with my meter it's showing like 14.7 for the output.

Anyways long story short on each time this happened when I have my headlights on (HID) and say I turn my blower on from 0 to 4 or.. turn on something with a large start up load my idle dips down and my headlights win flash the idle drops like 100 rpms almost..

However.. I turn the car off for a few and then start it up again and it's like nothing ever happened..

I have a video of this as well

[ubar legacy]

try load testing your battery maybe?
I dont think it'd be your alternator if its reading 14.7..

but i guess i could be wrong..

[Navi271]

when my alternator went it was somewhat sudden. It made a small whining noise for almost 5 months before leaving me stranded on the interstate. Does your battery light come on? I think it is supposed to turn on when the voltage dips down below a certain level.

[1-3-2-4]

no the battery light does not come on because it still gives out 14V it's only when I have loads on the car headlights, fog lights and blower on and then pressing the brakes..

thats when the headlights will turn off then radio and so on.

[02_Legacy]

Are you reading 14.7 volts at the alternator or the battery. There could be a bad connection between the two.
Or your voltage regulator could be freaking out on you droping the output when there is a sudden load.

[1-3-2-4]

reading from the alt output to the neg post on the battery

[Kraziken]

I think I'm experiencing the same thing. If I run into stop and go traffic with the HID lights on, radio. I'll get a dip in power, the radio and Defi gauges flip as if the car was just turned on. The rpms drop but I don't completely stall.

If I shut off the radio, I'm usually fine. I have two amps running two front speakers and a sub.

I've read that Foresters have 110 amp alternators versus the normal 90 amps in most of the other cars? Still checking to determine what I'm going to order as a replacement.

I found a 140amp replacement and higher versions, but they require additional wire and fuse to install correctly.

http://www.maniacelectricmotors.com/11058hiamp.html

I know I personally have a ton more electrical load added to my car, and the alternator I have now was replaced on a few years ago. I would think it would last longer, but I think the load is prematurely killing the alternator.

[1-3-2-4]

If you ever find out why that happens let me know!

[Kraziken]

Seems the 2006 Forester XT turbo models have the 110 amp alternators. I decided to order this one for now.

http://www.maniacelectricmotors.com/110ampmialfo.html

After I do the install, I 'll report back to see if it has fixed my problems.

[1-3-2-4]

Make sure it fits I know the plug changed just not sure what years

[Grafton]

^ I think it's still a 2 wire setup but a different plug

[Kraziken]

Well I have a 04 STI engine, so as far as I can tell I think it will plug right in. At least it appears that way from the Nasioc thread I read.

For the original legacy maybe not? I wonder if you could just change wiring connectors? I guess I'll find out soon enough.

[02_Legacy]

Ya if they both have the same number of wires I would think that you should be able to get a pigtail and splice it in place of your current connector, just make sure you hook it up the right way.

[Kraziken]

Well I should have looked a little closer before ordering. Although I couldn't find any pics and I was getting anxious to order.

The 3 prong plug from the Forester XT alternator will not fit our generation cars, and when I talked to the shop. They said wiring to make it compatible with the new alternator would not be cost effective. Not impossible, but a huge ordeal.

If I verified a bit more, I would have found this one.

http://www.maniacelectricmotors.com/hiou195ampsu.html


I'm selling the Forester XT alternator to my brother, who I verified today that he can use it.

[98bksarah]

As for the original question... HID lights use more energy on startup. They are similar to home fluorescent lighting..In that they use less energy overall. However the initial energizing load is greater than that of your standard halogen bulb. So, that combined with the blower and fuel pump and radio and yadda-yadda is "heavy" for the charging system which just seconds ago was dropping some serious amperage to spin the starter bendix. Voltage drop+ weak grounding+ high mileage alternator= what you are experiencing. Get some solar panels. Move to Brazil. Make AL-GORE proud. 2 cents worth

[1-3-2-4]

With a hi amp do you need to upgrade the output wires?

[02_Legacy]

With a hi amp do you need to upgrade the output wires?

I doubt it the wire going to the battery is pretty thick to start, and its not like you are going to be pushing twice the amps, you will only get a 30 or 40 amp increase.

[Kraziken]

IF you are able to just go to 110 or so alternator from the Forester, probably not necessary.

Directly thru the link maniac motors recommends doing the "Big 3" with their 140amp alternators.

Well I already did a grounding mod, so I didn't bother with changing that. The chassis ground is a pain in the rear to get to. Maybe after I swap and go away from the top mount intercooler I'll change that one for a thicker cable.

Pics of the new alternator and added power wire and fuse. And this was my issue. Since swapping the alternator, I haven't had any power drop problems.

https://sl-i.net/FORUM/images/imported/2011/05/P5010107-1.jpg

[dodik]

i can take a pic of my alternator H6 2002 it uses wider pulley but bolts in the same way i think it has a bit more power.

[GlennScott]

As for the original question... HID lights use more energy on startup. They are similar to home fluorescent lighting..In that they use less energy overall. However the initial energizing load is greater than that of your standard halogen bulb. So, that combined with the blower and fuel pump and radio and yadda-yadda is "heavy" for the charging system which just seconds ago was dropping some serious amperage to spin the starter bendix. Voltage drop+ weak grounding+ high mileage alternator= what you are experiencing. Get some peimar solar (http://www.shinesolar.net). Move to Brazil. Make AL-GORE proud. 2 cents worth
I have got bit different light system.. I am using led lights with solar panels. It is really working fine for me.

[Zangado1]

My parents bought my Leggy Wagon new in 1995,i got the car from them 2 years ago and about 5 months ago it just recieved it's 8th alternator. Most were purchased at NAPA and installed at our family trusted shop. I have kept all of the service history of the car that my father has kept,that how i know that this car eats alternators.....