Andrew.

iTrader: (4)

Hola,

For some reason my fc is losing its charge instantly after the car is shut off. At idle my volts fluctuate between roughly 11.1 and 12.3 volts, when cruising it goes to about 12.6-12.8 at max. Today in the morning it turned over barely but didn't start, so I went to jump start it and it read about 13.2 or 13.3 volts. The alternator is about 6 months old, battery has been tested about 2 weeks ago at kragen and passed the battery test and was in good shape. I did almost take this thing to shortblock and put it all back together and removed an aftermarket ground that went to the front of the uim to the firewall. What could be the problem? If its the alternator it does have a lifetime warranty, if its the battery i think i'll go for an optima redtop. Any suggestions? Thanks

-Andrew

Icemark

Your alt has failed or is wired incorrectly.

At idle the voltage should be at least 13.5 volts, and closer to 14.4.

You won't even charge the battery unless you have at least 13.5 volts, and you are running on the battery at anything under 12.6 volts.

Impreza2RX7

When my car was doing this, the voltage regulator in the alternator was dead.

Andrew.

iTrader: (4)

I suspected it was the alternator, its just that last time i was sorta having this problem I went to go get it checked it came out good, but the guy told me if you can make the machine read that the alternator isn't working i'll trade ya. So if it reads good again when it is obviously bad how can i short it out? Thanks guys for the help.

-Andrew

WAYNE88N/A

Since you mentioned removing that "aftermarket" ground, I'll bet you have an insufficient bonding circuit for the alt.

Try this: Get a meter, put it on ohms, and check the resistance between the alt body and the negative batt terminal. If it's more than about 1 ohm (should be close to zero, really), you have a bonding problem. Notice I didn't say "grounding" problem.

Make a good quality bonding jumper using at least 10 AWG stranded copper wire with crimped ring terminals on the ends. Install one end at the alt's mounting hardware (I used the back of the big bolt on the bottom), and the other anywhere near the back of the engine (rear rotor housing, rear side housing, etc).

You also have to make sure that the tranny-to-firewall bonding jumper is still there and in good condition. If in doubt, remove it and clean up the bolt locations...

If your problem is in fact a bonding thing, you should see good results doing the above...

Andrew.

iTrader: (4)

Wayne,

It was doing this before the ground was removed as well. Update is i went to kragen and they tested it out 3 times for me because i wanted to be 100% sure and it came out perfect. He told me to check out the voltage regulator, ergh, this shall be fun are there anyways to check it without ripping apart the alt? Thanks

-Andrew

WAYNE88N/A

There are some functional checks for the alt and associated wiring in the FSM that go pretty in-depth, if you want to perform them. Body electrical section, IIRC (although that doesn't sound right, does it?)...

Andrew.

iTrader: (4)

haha, i'll read the my fsm today. on a different note though, where should i source my vacuum for my fpr? On a motor that has no rats nest but has the cold start assist (the 2 yellow plastic vac lines). Thanks for the help again Wayne.

-Andrew

Andrew.

iTrader: (4)

I have yet to find my fsm its probably somewhere in my pile of fc parts but i did find out something weird today and i'd like to know what it means.

1st weird thing was i put my alt back together and everything, started the car up with a charge from my moms 96 ford windstar and it started up fine and read like 13.8-14v so i start it up for abit, then shut it off, go to start it again, turns over for 1 sec then not enough voltage to turn it over, i go to my engine and see i never plugged in the alternator connection (which is a bit loose for my liking), so i plug it in, reads 11.8 volts on my dmm but doesn't turn over, damn.

2nd weird thing was that i swapped batterys from the van to the fc. The vans battery is a bit bigger but it started the car right up and read 14.2 volts. I shut it off turn it on, reads 12.8, rev it up a bit reads 14.2 again, shut off then keeps doing the same thing just to recheck.

Just a few facts about the batterys. Before i jumped it, the battery read about 3.8 volts, after it was jumped, it was in the 13 range. The van's battery before it was turned on was 12, when it was on it hit high 13's. When the van's battery was in the fc, before it was started it read 12, after it was started, high 13's, but according to my dmm after started it read 14.2 and rouhgly the same with my guage.

I dunno, i'm confused, weirded out and tired.

-Andrew

WAYNE88N/A

Umm, you can't drop a lead-acid battery to 3.8v and expect it to ever be the same again.

It actually sounds like the charging system is doing what it's supposed to do (once you connected the alt's plug), and the batt is the weak link now...

Andrew.

iTrader: (4)

Ahh, cool, Optima redtop here i come!