Good day guys, so this is my problem:

My step sister has a civic 93 si vtec but, she installed a 2000 si d16y8 but she kept the old intake manifold so all the wirering stays the same to remain obd1.

About 1 month ago she told me that the battery light was coming on at high rev... so i found an alternator (new) for her car... When i went to get the alternator for her i told the guy that i was for a 93.. then just before i installed it i had a flash that it would maybe not be the right one since the engine is a 2000.

But since the wirering stayed the same the alternator outpout would still be fine? right?

Now she's got her battery going dead again but without any sign of a batt light in the dash. One strange thing is... she had a booster pack to boost the car since there was no power to start and sometimes even boosted it wouldnt start at all....

But on a compression start it was starting fine.

I dont think it's the alternator. What do you think of removing one of the battery wire on of the pole while the engine is running? If the engine dies right of the bat well that would mean that it's not charging at all?

Also, she told me yesterday that she got a new battery installed and it's getting drained again.... But at first, after it was installed the car was starting normally.

Can you help me on this?

thank you guys

 

what engine is in what car?

 

it's a d16y8 in a civic 93 that had a d16z6

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by marcus029 &raquo;</TD></TR><TR><TD CLASS="quote">When i went to get the alternator for her i told the guy that i was for a 93.. then just before i installed it i had a flash that it would maybe not be the right one since the engine is a 2000.</TD></TR></TABLE>

If the alt conector (green plug) is from the 93, the new alt you bought will work.

 

Charging systems from both engines are near identical. Put this on your list to check, if you can, bench test the alternator to see if it is in fact bad. If the autozone around you has more than a load test machine, ask them to test the diodes as well, to see if any diodes failed. Always find out what failed, so you can work back you why it failed.

Since the charge light is on, I would suspect a faulty regulator if the alt is infact bad since the alt connector has to be plugged in for the dash light to illuminate. The battery light does not indicate current, you could be charging 14.1V @ .1A and the light will not come on, thats why people bench alternators, just for reference.

Most alternator problems arise because of other system problems. These can include:

1: Poor power/grounds to and from the battery to the engine/transmission.
2: Poor chargeback wire condition/connection to the underhood fusebox.
3: A battery that is old/worn out that will not take a fast charge easily.

I would check those in order to start. High resistance in the chargeback circuits and battery, including the grounds will result in the produced current to find an alternative path home, normally by shorting the diodes and stator assembly. This is why many people say "check your battery" too, but do not understand why.

If your power/grounds are weak and wires are poor, replace them, they are cheap. Larger diameter wires helps, Honda does use small grounds...

Check your chargeback wire to the fusebox and inspect for corrosion/damage.

Load test the battery at around 1/2 to 2/3 of the rated amperage. BE VERY CAREFUL doing this as a bad battery may explode, which would indicate the problem in a bad way. If starting performance is very sluggish/unpredictable when cold or the battery is very old, it would be safer to buy a new one.

If the battery holds a charge when charged, but discharges overnight, I would suspect a failed diode in the chargeback line, which allows the battery to discharge into the stator. This would require replacement of the unit.