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I replaced the alternator

1K views 9 replies 4 participants last post by  Submariner409 
#1 ·
So I'm driving home from work and the battery light comes on and as I watch the volts drop the car eventually dies. So I go home on the hook and feel fairly comfortable that I need an alternator as the battery is only a few months old. I order up a lifetime guarantee alt and charge the battery and start twisting wrenches.
Now I'm not going to say that this was the most obnoxious R & R I have ever done but, yes I am going to say it. This job really sucked. The alt would only come out one way, thank you for the removable panel, and the bolts had to go back in a specific order. Even the exhaust manifold was clearanced at one location to allow a bolt. Yikes.
So the two day living Hell installation is complete, battery is charged, and the car starts. 14.4 volts at idle, the car runs and drives, but, the battery light is still illuminated. And the DIC keeps telling me to service the charging system. And I worry about going home on the hook, again.
What step did I miss? The FSM doesn't provide any other steps, so what have I left out? Please?
 
#2 ·
So I'm driving home from work and the battery light comes on and as I watch the volts drop the car eventually dies. So I go home on the hook and feel fairly comfortable that I need an alternator as the battery is only a few months old. I order up a lifetime guarantee alt and charge the battery and start twisting wrenches.
Now I'm not going to say that this was the most obnoxious R & R I have ever done but, yes I am going to say it. This job really sucked. The alt would only come out one way, thank you for the removable panel, and the bolts had to go back in a specific order. Even the exhaust manifold was clearanced at one location to allow a bolt. Yikes.
So the two day living Hell installation is complete, battery is charged, and the car starts. 14.4 volts at idle, the car runs and drives, but, the battery light is still illuminated. And the DIC keeps telling me to service the charging system. And I worry about going home on the hook, again.
What step did I miss? The FSM doesn't provide any other steps, so what have I left out? Please?
I have the EXACT same problem - and had the same nightmare changing the alternator on my 2000 ETC. My buddy, who checked with a mechanic buddy of his, told me something about it being caused by a 5v Exciter in the new alternator, where the old ones had a 10v Exciter, and it messes with the computer. I've had my alternator in since last fall with NO issues that affect performance. I have to reset the DIC code every time I start it and my battery light is on all the time. Just a PITA. He said I could search out a different alternator to fix it, but I'm good hitting a button rather than doing that job again.
Gonna follow this in case someone has an easier fix tho.
 
#6 ·
Hey Geoff,
I know I can change it faster now that I have gone through that nightmare, but how do I know it has the correct exciter?
So you click on the warning on the DIC to make it disappear, I do that daily, is there a DTC that you get?
=======================
so - can we assume you purchased an auto parts store - "house-brand" - "lifetime warranty" alternator?

if YES - that was a BIG mistake - and the chances are near 100% you WILL be replacing it again - and again -

these are NOT rebuilt or remanufactured -
they are "fixed" - the cheapest way possible -
often with used parts - or the cheapest generic new parts available -
then painted - and put into a new box -

the paint and new box are the most expensive components of this alternator -
which is why they are so cheap for a "lifetime warranty" unit -
you'll NEVER see a shop use one of these - ESPECIALLY on a Northstar powered Cadillac -

with all that said -
you can buy a BRAND NEW - not rebuilt/reman - genuine ACDELCO 3351054 -
for LESS than $130 - including shipping -
2000 CADILLAC ELDORADO 4.6L V8 Alternator / Generator | RockAuto

DO IT RIGHT - DO IT ONCE -
 
#5 ·
I'm not sure how to determine if it has the correct exciter. I stopped at my buddy's word and realized that I wasn't having any performance/charging issues, so truthfully I didn't look into it any more than that. I'm also just assuming he was correct in his diagnosis. He's usually very good, but COULD be wrong I admit.
Yup, I hit the info reset as soon as the "check charging system" warning comes up on every startup.
I haven't even checked my DTC codes yet - haven't had a need to since then. My ETC is a daily driver, so I pretty much just fix problems as they come up.
Sorry I can't be of more help! Maybe somebody that's more competent in this area can chime in?
 
#7 ·
Well when I was on Amazon reading reviews on genuine AC Delco alternators there were many reviews of these China built alts that were failing out of the box so I went to a local dealer, Advance Auto Parts, and they brought it in for me. Your blanket statements regarding the aftermarket may be true sometimes, but not always. No company is going to stay in business if they continually replace broken/defective items and survive the bad press from that.
How would anyone know in advance if the Rock Auto alt has the correct exciter?
 
#9 ·
Well when I was on Amazon reading reviews on genuine AC Delco alternators there were many reviews of these China built alts that were failing out of the box so I went to a local dealer, Advance Auto Parts, and they brought it in for me. Your blanket statements regarding the aftermarket may be true sometimes, but not always. No company is going to stay in business if they continually replace broken/defective items and survive the bad press from that.
How would anyone know in advance if the Rock Auto alt has the correct exciter?
=====================
YUP - you're right - and I'm wrong -
you should stick with the rattle-can-remans -

by the time you get a good unit - with the right exciter (what ever that is) -
you'll be able to swap an alternator in your sleep - blindfolded - with one hand tied behind your back -

but - what do I know -
I only speak from several DECADES running a shop -
and 16 YEARS on this forum -

good luck -
 
#10 ·
In an alternator "excitation voltage" is that DC voltage and current fed to the field in order to create magnetic flux. It varies in value by car, application, electrical system, whatever.

The aftermarket "one wire" alternators usually use an excitation voltage of 10 or so, which is why you need to sometimes blip the gas pedal to "turn on" that type of alternator.

Ah, so - here's a quick Google search .............

google.com/search?q=automotive+alternator+excitation+voltage&rlz=1C1JZAP_enUS905US905&oq=automotive+alternator+excitation+voltage&aqs=chrome..69i57j0.14763j1j8&sourceid=chrome&ie=UTF-8
 
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