EFyew

i'm looking for a direction to head, because at the moment i'm pretty well stumped.
i'm working with a DPFI d15b1 motor in my 1989 Civic Hatchback.
lol, my problem is that i've gone through 3 alternators in the span of about 6 months. the time is so lengthy do to the fact that it's hard to get around to troubleshooting due to work. but ...
ive had each of these three alternators tested and replaced with refurbished ones.
each time, they go bad. not bad enough to make the car quit running, but bad enough to not charge my battery fully and cause my lights to dim when the brake pedal is pressed or while my stereo is playing loud. sometimes you can even tell it flicker with the beat of the motor.

ive cleaned, moved, and even made sure the ground to the battery was tightened. replaced the alternator 3 times. gotten the battery tested. charged the battery over night myself. had autozone de-charge the battery, and recharge it, and had autozone test the alternator in the car now and they even said its bad too. ive changed my ground for my stereo amp to from the bolt under the back seat cushion to the shock tower (no change). rewired my stereo. put in a new stereo. re wired my speakers. put actual tips on the ends of the ground wire and power wire to my amp. looked to see if there were any loose ends at the brake pedal switch. check my bulbs. and replaced my burnt out reverse lights (which still don't work) and still no change in the flicker of ALL my lights in my car. :/

so if you can lead me in another direction. please make any suggestions as to figuring out what is making these alternators go bad.
thanks in advance.

Former User

Are having problems now?

EFyew

yessir I sure am.

Former User

Measure voltage across the two battery posts under these conditions:

1) Key off

2) Warm engine idling with all electrical accessories off

3) Warm engine idling with high beams and A/C max on.

EFyew

if I don't have A/C, just put the fan on full blast? correct?
I'll get to these three answers as soon as soon as possible.

Former User

This^ is fine.

EFyew

cool beans, I'll let you know as soon as I can.

EFyew

battery test
ignition off - 11.96v
all accessories off, car running at idle - 14.25v
all accessories on, car at idle (fan on high, headlights and high beams on, stereo volume at 15 with stereo subwoofer amp on) - 11.63v

4drEF

On the last scenario - what's it do with the stereo off?

blueprince4ever

try other tec

EFyew

I'll get this answer for you after my commute to work this afternoon.
are you agreeing with 4drEF?

4drEF

Here's where I'm going with it -
First, your battery seems a little low. After the battery has settled (car has been off for a while) it should read about 12.4~12.8 on a good charge.
How old is the battery? Typical battery life is about 3 years.

Your idle voltage seems ok. That is actually the alternator voltage you are reading. It should be about 13.3~14.8. Higher than 14.8 would be reason for concern.

Your load test is what is not looking great. With stock accessories on, you should still be reading close to that number in the idle test. It should only drop about .5 volts. If it's lower, then your alternator is gone and you have a problem. This is also relative as to why your battery is looking a little low. Sometimes it's as easy as cleaning up all the grounds (pretty common). In your case, your audio equipment might be drawing too much off that alternator and that's why you are killing them.
So - do what it take to disable the audio and then redo the load test with stock accessories on. You will first need a new alternator.

EFyew

the battery was bought no more than 2 years ago. brand new.

as far as the grounds, the negative is brand new with a year. it's tight also. no problems there. as for where the ends are connect (referring to the little wire and the larger wire) the thickest is bolted on the bracket above the tranny and the smaller of the two is bolted just above the headlight assembly.

as for my stereo grounds, my head unit is wired to the stock stereo ground wire. my amp ground is no longer than 2 feet and is bolted from the top of the shock tower, to the amp (of course).
are there any others I need to be aware of?

so basically.
disconnect all of my stereo or just the amp end?
get a new alternator
then check those three voltages without my stereo/amp wired?

crvtectim

The biggest mistake people make with grounds is not taking care to sand completely through paint and primer down to bare metal. Make sure you've done so.

EFyew

while doing some research on all of this, I found (unknown resource) that the shock tower was a good place to ground.

also that the threaded inserts, on the slopes at both the insides of the headlight structures, were meant for grounds also. stating also that the valve cover ground is supposed bolted here (on the cam gear side of the engine).

there are two of those threaded inserts and I bolted the smaller ground wire lead off the negative terminal of the battery to the opposite side one.

can u second these spots as to being optimal grounding locations?
that is if you can understand my explanations. lol

crvtectim

Sure man, you should also have a ground at the transmission. There's a bracket. I moved my valve cover ground to an empty bolt hole in the head just above the intake manifold replacing it with a heavier gauge wire. You can pretty much pick and choose where to run grounds but some people fool themselves into thinking they sanded through the paint as soon as they hit primer because it appears to be bare metal.

EFyew

ah, i know this bracket. that's where the thicker of the two grounds is bolted from my negative battery post.

is the smaller of the two stock wire, really necessary for the valve cover ground. (running from the head stud, to the valve cover?

ill be sure to get to this as soon as possible. busy 10hr a day work schedule so most likely this weekend.

ZCHondaCRX91

I have this same problem, and once you really get into honda alternators you find that they have two-modes. One is at idle or cruising (there is a list of criteria) which is low load so the alternator is either barely on or 15 amps at the most, and under heavy load it will put out 30-60amps as needed. The problem is it's not switching to high-output mode. Check the white/yellow wire on your alternator plug, with all the loads on and it should be 6-8 volts to indicate that the ECU is switching it to high-output mode (ECU will ground it for low-output mode). If you know someone with an Ammeter test the alternator output with no load and with light and heavy load. I've spent 2 years trying to figure out my problem, I've talked to 20-30 year honda mechanics and they can't even figure it out. Hopefully it's something simple with yours.

4drEF

Grounds aren't only there for your electronics. They are also there to prevent corrosion effects between materials inside the engine.

From battery, you have a thick ground to chassis. Then you have a thick ground going from chassis to transmission, chassis to thermostat housing, and chassis to head stud. Some of the Honda motors even have a ground going to the valve cover.

EFyew

is this connector something you can get from a local automotive store or hardware store like autozone, advance, lowes, o'reillys, napa etc?

ZCHondaCRX91

Some stores might have an ammeter or charging system tester capable of measuring amperage. If I were you I would get a good used OEM alternator and see if the problem persists.

Former User

So what's the answer?

4drEF

He's still commuting. Car turns off so the commute is now a 2 day walk.

mysunny2k

Find out if different alternator from different car has different rating, then, get the replacment part for your car.