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Electrical Gremlin with new alternator

1894 Views 15 Replies 6 Participants Last post by  dcspider, 
jayraza
Hi all, there's so many knowledgeable members I figured I'd post this problem here as well:
TL;DR my stock alternator worked better than my new H/O alternator. All the info is below.

I had My 09 Eclipse GS 2.4l's stock alternator replaced because the pulley was making squealing noises on cold starts. The alternator performed fine as far as keeping up with the vehicle demands other than rolling up the windows. (this would make my voltage drop from 14.0v to 13v momentarily while using either the driver or passenger switch. The voltage drop happens AFTER the windows are up, not during the process. The older alt voltage would idle at 14.5v on cold starts and then drop to 13.8v-14.0v after about 5-10minutes and increase to 14.5 while driving. The car has never acted like it wants to stall with my stock squealing alternator.

Fast forward to now: I have a 250 amp H/O alternator from PowerBastards that is having trouble since day 1 (I think) keeping up with basic vehicle demands. The window problem is still there, only worst now.. the vehicle acts like it wants to stall if I keep the window switch pressed after the window is up. Sometimes when I come to a complete stop, the car sounds like it's about to stall. There has also been more than one occasion where after starting the vehicle on a warm start, the voltage keeps trying to lock to 13.6v and the car almost stalls and the voltage shoots up to 15v and stabilizes to 13.6v again. I have since changed the domestic battery to a stronger one (690cca, 850 CA) and have done the big 3 upgrade. Window switch problem is still there, alternator is still acting the same. My car starts up much quicker now though :) one upside.

This alt acts different from my stock one though. On cold start the idle voltage is 14.5v, it drops to 13.6v after warming up and my problems start. Any demand in the circuit, causes a weird fluctuation in voltage ie: if I turn my fan on full blast or turn on brights I can feel the vehicle physically struggle slightly and the voltage output reads 14.7v - 15v sometimes higher and then it stabilizes to 14.0v before dropping back down to 13.6v. This isn't my first H/O alternator. When I first got the new alternator, I tried my system for shits and giggles and the car almost stalled with voltage dipping to 12v. So Ive taken it out the circuit. Still has problems. I've owned a 200AMP alternator that pushed my sound system without a secondary battery and the voltage would always stay above 14v. This was on my old camry though.

These are my observations. At this point my stock alternator performed better than this H/O alt. Am I missing something here? What's wrong with my electrical system? Dealing with PowerBastards is a PITA!! I am trying everything to give them the benefit of the doubt. I almost want to put my stock squealing alt back on :/ I was told my a alternator guy once that you never want your car voltage below 14v while it's running... welll shit.
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jayraza
Incase anyone wonders, I upgraded to a higher output alternator for my sound system that now has its own dedicated battery. I left the sound system out the circuit until I could figure out what was wrong with the domestic circuit. So all these problems are happening without my system being in the circuit. I also seen in my research that a guy had similar problems as me but it turned out to be his ECU... do these cars regulate voltage through the computer?
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pcfreak4
jayraza said:
I’ve also seen in my research that a guy had similar problems as me but it turned out to be his ECU... do these cars regulate voltage through the computer?
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Yup, they do, you’re right on the money there
It’s obvious that the problem is your new alternator itself, it doesn’t really seem like very high output voltage wise, maybe amperage is what it’s good at
But in my opinion, I haven’t seen an issue with power delivery with my stock alternator even with a sound system, I mean it’s not some wild crazy powerful sound system but it’s decent and the alternator has no issues keeping up
I know what you mean by the voltage sag from the draw of continuing to roll the windows up, I have a habit of doing this as well sometimes to make sure the windows really are fully up, I know it’s not best for the window motors tho to do too much

So the PCM/ECU actually commands the controller inside the alternator to put out certain amounts of power that it requests, obviously that’ll probably work best with the original alternator, it seems as though your aftermarket one isn’t cooperating properly with what the computer is requesting
There’s not much you can do other than get rid of that alternator and get one that actually does cooperate and work properly
Maybe you could have some place rebuild or replace just the pulley on your stock alternator
It’s not uncommon for good quality alternators to actually last 200k miles
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jayraza
pcfreak4 said:
Yup, they do, you’re right on the money there
It’s obvious that the problem is your new alternator itself, it doesn’t really seem like very high output voltage wise, maybe amperage is what it’s good at
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I've been suspecting the same, I'm just trying everything so that when I leave a review for PowerBastards on BBB, it's honest and hopefully others will avoid this company. Their rep Mike Savino has been giving me the run around and has been blaming issues first on my running battery, then my second battery, then just flat out says it could be my car... but never their alternator. He proceeds to tell me to take it off and test it. I'm not inclined to remove and mount an alternator personally so I have to pay someone to do the work. He must think I'm made of money. He also comes off very condescending, just a heads up for anyone that's in the market... AVOID.

I purposely left out certain details when talking to him, like having my secondary battery disconnected to see if he blames that, and he did.

pcfreak4 said:
So the PCM/ECU actually commands the controller inside the alternator to put out certain amounts of power that it requests, obviously that’ll probably work best with the original alternator, it seems as though your aftermarket one isn’t cooperating properly with what the computer is requesting
There’s not much you can do other than get rid of that alternator and get one that actually does cooperate and work properly
Maybe you could have some place rebuild or replace just the pulley on your stock alternator
It’s not uncommon for good quality alternators to actually last 200k miles
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I'm not sure why I didn't think of this. I will take your suggestion and have my old alternator rebuilt here locally with higher amperage output. That's how I had my first H/O alternator done and it was AWESOME. That thing would keep up with anything you threw at it. It's not the same experience this go around..

Thanks for the reply.
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Sabertooth^2
Out of curiosity, how are your ground and power connections? Having them in prestine condition, and removing the paint at them goes a long way.
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pcfreak4
Sabertooth^2 said:
prestine condition
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Pristine lol

But I agree, cleaning those up and maybe adding the "big 3" would do more for you for car audio power needs

I remember researching and finding out that there really weren't any quality high output alternators even available for our car

My guess is the one you got claims to be, but it's really the same rebranded Chinese junk you'd get from Autozone as the cheapest part available, and you still got a faulty one
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jayraza
Sabertooth^2 said:
Out of curiosity, how are your ground and power connections? Having them in prestine condition, and removing the paint at them goes a long way.
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I’ve only changed the ground from the engine to the chassis and from the battery to the chassis. There’s a few other smaller grounds around the fuse box and ecu area that look like they may need some TLC. I also noticed the original alternator charging wire looks corroded at the terminal (my big 3 wire is essentially bypassing this wire, I just never removed it.) I will take care of these soon to see if it improves my electrical overall.
pcfreak4 said:
I remember researching and finding out that there really weren't any quality high output alternators even available for our car

My guess is the one you got claims to be, but it's really the same rebranded Chinese junk you'd get from Autozone as the cheapest part available, and you still got a faulty one
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You are absolutely correct here. You have been spot on since your first post. I also spoke with Tony from mechman alternators and he essentially said the same thing you mentioned in this post above, more or less. That’s part of the reason mechman doesn’t carry our alts anymore. I’ll post what Tony sent me below.

Singer claims to have an alternator that is capable of producing 140 amps at idle, but has not responded back to me since I asked how the alt was regulated... so we will see about it. Thanks again for your inputs

Tony’s email:
Some manufacturers use different companies to build their alternators. It’s simply a matter of supply and demand. The Mitsubishi style(not just your car brand name) has very very little aftermarket support so that makes the parts expense to get or even attain. Second, from what we’ve tested, the parts that ARE available are simply not made to do what we need them do AND be able to ethically warranty that part for 2+ years.

We do have a few Mitsubishi style cases that we use, but we use completely new internals for them to fit and ONLY because they have a decent wide spread application to other vehicle applications. We’ve discontinued many of the old Mitsubishi ones we used to offer because even though we did all we could to make them great, they still had a fail rate/return rate that was unacceptable for us.

We certainly don’t have the long list of applications like other manufacturers do, but we simply cannot sell a product we do not 100% back. Specifically speaking of some of the small case units we see being advertised. They advertise them at 270-320+, but what they don’t tell you is that the vehicle will charge LESS or not even at all vehicle idle speed and to attain that 270+ rating the vehicle needs to be turning 3000 rpms.

We build ours for plug and play stock style operation short of a belt and cables in most applications. We do not want to build a product that will only mask one problem to eventually create another.
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Hopefully this will help someone else. I’ve also read somewhere that if you upgrade your alternator to a H/O with an external regulator, voltage is much more stable and things seem to work as normal. I haven’t found any company doing it, though. I’ve emailed a few that are big in the audio world, I’ll post back if I find out snything
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Sabertooth^2
Oh, definitely fix those bad grounds. All sorts of funky stuff can happen when those are weak
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jayraza
Sabertooth^2 said:
Oh, definitely fix those bad grounds. All sorts of funky stuff can happen when those are weak
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Makes sense, they looked questionable.

Also, I wanted to update this thread because I may have fixed my problem that’s related to a lot of high output alternators for our cars. I tried what is mentioned below and my voltage is stable at idle at 14.0-14.2 volts after the initial cold start where voltage temporarily remains at 14.5v. I spoke with a rep from usalternators and they were nice enough to pass down a tip I’ll post the direct quote below:
I can give you a tip to maybe getting steady voltage. Your car is simple PCM control. The “C” terminal grounds to lower the voltage on your alt. If you cut or remove that wire from your connector to the alternator it should give you steadier voltage. The below pinout is looking into the regulator of the alt. So on the plug the most left wire looking into the alt you would want to disconnect. The second wire from the left looking into the alt you could put a diode or a resistor inline to raise voltage. Leave the other 2 LMP and FDB wires connected. We would make you a harness but I do not carry these plugs or have the ability to get these plugs for a plug and play solution so you would need to hard wire on the vehicle.
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102335

After applying this my car is no longer having problems. Everything is working like it’s supposed to. I’m going to test this for now and stand by on the outcome. Thanks all

edit: I only disconnected the ground wire. I did not disconnect anything else.
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pcfreak4
So you disconnected the ground and then what to the sense wire?
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jayraza
pcfreak4 said:
So you disconnected the ground and then what to the sense wire?
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I forgot to mention that I didn’t do anything with the sense wire. I left all that alone. I only disconnected the ground. I still experience spikes in voltage (from 14.2v to 15.0v sporadically when harder notes hit at full tilt with my sound system, but the car is actually running better. I can play my system at comfortable levels with no issues and all vehicle components work as well
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Mevo
How big of an audio system did you attach if you don’t mind me asking? I have a company on standby wanting to put a couple of subwoofers where my backseats once were, but after seeing this post, I’m worried about how well our stock internals (without the big three) could handle that additional load of 2 10” subs attached to a 400W (300amp) amplifier.
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jayraza
Mevo said:
How big of an audio system did you attach if you don’t mind me asking? I have a company on standby wanting to put a couple of subwoofers where my backseats once were, but after seeing this post, I’m worried about how well our stock internals (without the big three) could handle that additional load of 2 10” subs attached to a 400W (300amp) amplifier.
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I’m using a skar audio RP-1500.1D for my two 15s. It’s rated at 1,500watt rms power. I also have an additional 800 watt sound stream for my mids and highs with a second battery powering the system. The alternator I bought is rated at 250 amp max output with about half of that at idle according to the manufacturer.

I used my system a few times with my stock alternator (without a second battery or big 3) and I could turn it up pretty loud while driving.... you could forget about that at idle though. Your system won’t demand as much as mine. Might still be questionable at idle during full tilt. If you use a second battery and or capacitor I think you’ll be fine with those demands, you might be fine just with the stock alternator, but extra power reserve for it definitely helps. I would def ask the car audio guys for their professional opinion as well

Edit for extra info..
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Mevo
jayraza said:
I’m using a skar audio RP-1500.1D for my two 15s. It’s rated at 1,500watt rms power. I also have an additional 800 watt sound stream for my mids and highs with a second battery powering the system. The alternator I bought is rated at 250 amp max output with about half of that at idle.

I used my system a few times with my stock alternator (without a second battery) and I could turn it up pretty loud while driving... you could forget about that at idle. If you use a second battery and or capacitor I think you’ll be fine. Might still be questionable at idle during full tilt
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Appreciate it! I’ll definitely be looking into your suggestion after seeing the migraine your alternator inflicted.
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14tthurston
I know this is an older post but I was wondering if you every found a full resolution to your problem. I have a big system in my car with a gp audio 270 amp alt. I have 4 0 gauge charging wires running back to a 96ah headway bank in the back and that is powering a sundown 7500 watt amp. I’m still running a battery up front as well and ran a circuit breaker between the charge wire for the alternator and the stock battery so I can isolate them when I park the car. The issue I am having it that when I am at idle, the voltage will drop down into the 12s even without the system playing and the battery light will come on. Also my rpms will fluctuate a little from 750 sometimes down to around 500rpm. If I rev it up the car the voltage will jump back up to around the 14.2 and site there for a bit and then will drop again. When I’m driving and have a load on the motor the voltage stays a consistent 14.4 even with the system at full tilt. My question is did anyone try running an external regulator? And if so did that help with your voltage at idle? I know my wiring is not an issue because I went a little over kill on all of my charge wires and my grounds and they are all down to bare metal. Any input would be much appreciated.
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dcspider
I think I have finally found my ghost battery issue. The engine wants more power and is clogged. After years of experimentation I can't find any other issue that our engine over time wants to perform but degradation of the catalytic converters is the issue. They got to go, get the magnaflow kit or build your own, stop OEM replacement.
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