The gayest voltage drain ever

[holemilk00]

Ok guys, so I'll try to be brief but informative.

93 vert KA-T

So the car turns to 7500rpm all day. Recently it left me stranded at night because it was just completely out of power.


Its a fairly new premium alt. so I took it off and had it bench tested, everything checks out.

Checked my battery, everything checked out.

Here is the weird thing now. The car runs great on a full battery charge and the lights OFF (for a limited time). If I turn the lights on and do a pull in the car it breaks up at around 5500rpms. Turn the lights back off, car runs great.

Drive the car around just at the speed limit with the lights off and it will at some point drain the battery, and over take the alt. and begin to shut down with no power.


Now things I've checked.

All the ground connection continuity
All the power supply wires for the headlights (among other things)
I've rewired half of the car looking for something grounding out
I've checked for blown relays
I've checked for wires that could be rubbed through

I'm stumped. Any suggestions?

[Om1kron]

try replacing the relay for the headlights, or have your battery bench tested to make sure it's not on it's way out.

[holemilk00]

try replacing the relay for the headlights, or have your battery bench tested to make sure it's not on it's way out.


I'll check/change out the relay for the lights tomorrow. Thanks.

I've already had the battery tested, its good. Even still shouldn't a car run with the battery disconnected once its started and running being just on the alternator?

[apex]

I'll check/change out the relay for the lights tomorrow. Thanks.

I've already had the battery tested, its good. Even still shouldn't a car run with the battery disconnected once its started and running being just on the alternator?

only if the alt is good if its bad it the car will die
but since u said the alt is good it should stay on

[redsx13]

try replacing the relay for the headlights, or have your battery bench tested to make sure it's not on it's way out.

neither one of those would cause it. If the headlights where pulling too many amps i.e one of the relays shorting out, it would blow a fuse. If the battery was bad the car would still run fine...in theory.

holemilk00 , in order to narrow things down a bit, simply disconnect your battery while the motor is running, if it stops running, you need to look toward you alternator/lower harness.

what wires did you replace?

[holemilk00]

holemilk00

what wires did you replace?

The car is on quite a bit of electronics:

AEM EMS (map based)
AEM Peak and Hold injector controller
FAL twin slim fans (On its on Bosch relay)
Aeromotive A1000 fuel pump (On its on Bosch relay)
Greddy Full auto turbo timer
CD player of course


As for wires I've replaced, since I've owned the car I've just about rewired the entire thing other then the upper engine harness, which had to be modified to add the above listed items. But the car ran fine for the last six-seven months and then this problem. As for what I've went through since this, I've completely rewired anything to do with the lighting on the car, I've gone back and redone/checked the wiring for the 5spd swap, I've doubled up my grounds for the fuel pump and fans, and I've completely redone the radio and turbo timer wiring just in case.

I'm going to go and pull the lower harness today and go over it with a fine tooth comb.

The thing that confuses me so much is in the last few months I haven't changed anything on the car that was electrical, I changed from triple projectors to bricks but it was just a plug and play scenario and I've even went back to the triple projectors to see if that fixes it and it doesn't. I just banging my head against the wall now.

[holemilk00]

I should also add that EVERY connection on the car is soldiered and in Rhaychem glue shrink tubing and then wrapped from there.

[holemilk00]

Ok things I did today:

Replaced battery with fairly new optima redtop out of my other car
Replaced all the ground leads and made sure there was good contact for them
Deloomed the ECU end of the harness to check for damaged wires, nothing.
Checked the wiring AGAIN for the 5spd conversion that had to be done by the fuse box for the cluster to work.
Found out that my car will NOT run with the battery disconnected because of the way my ground is for my battery relocation and the AEM EMS. (Per a graduate of Kettering Tech)
Pulled the lower harness and went over it with a fine tooth comb looking for anything that looks fishy, nothing (this harness was new on the car six months ago from nissan)

I'm stumped again.

[brokeAs240sx]

What are your voltages @ the battery with:

- the car on @ idle
- while cruising @ the speed limit (where you noted even w/ the lights off, it will die eventually)
- with the headlights on

How is the battery relocation wired? Have you tried moving the battery back to the front (I'm guessing you can't sicne you probably have a FMIC)? It's always best to make things as stock as possible when diagnosing this stuff.

[slothonaleash]

Just support your voltage drain and treat it like a normal drain. There's nothing 'wrong' with your voltage drain per say, it's just going to need a little extra support from you to help it through life's extra struggles. Though it may seem tough at times, your homosexual voltage drain will grow up to be a well adjusted, confident drain if you give it all the support it needs.

/

[holemilk00]

What are your voltages @ the battery with:

- the car on @ idle 12.03 by multimeter
- while cruising @ the speed limit (where you noted even w/ the lights off, it will die eventually) 11.89 by AEM serial port gauge
- with the headlights on 11.60 by AEM serial port gauge

How is the battery relocation wired? Have you tried moving the battery back to the front (I'm guessing you can't sicne you probably have a FMIC)? It's always best to make things as stock as possible when diagnosing this stuff.

As for the battery relocation, its a Moroso relocation kit, so its 0 gauge for the power/+ terminal to the front of the car, and a ground that is 4 gauge, running to the engine block, with 6 gauge leads immediately within 4 inches of the negative terminal, and six other spots along the route to the block.

I moved the optima battery up to the front of the car and kinda balanced it up there and hooked it up and started the car, after it running for about 15 minutes at idle the car sputtered and shut off.

[brokeAs240sx]

just from ur response to the car on @ idle, you have something wrong w/ your system BEFORE you even mention the headlights.

w/ car on @ idle, you should be @ 14v.

If your car is same 12.03 or whatever w/ car off, then the charge from the alternator isn't reaching the battery.

Doesn't sound like a drain but more like something is miswired.

Make sure the lil ground wire (very small wire) for the alternator is hooked up, alternator plugged in, and run a custom (amp wire or whatever) from the alternator to the battery.

The battery should not JUST ground w/ the block, but the chassis too. Not sure how you have everything hooked up w/o pictures.

[holemilk00]

Doesn't sound like a drain but more like something is miswired. I was thinking the same thing at first, but then I thought, why would it turn up now? Why not months ago when I first got the car back on the road? Could it be possible that something in the plug of the alternator is bad? Letting the alternator still bench test fine?

Make sure the lil ground wire (very small wire) for the alternator is hooked up, alternator plugged in, and run a custom (amp wire or whatever) from the alternator to the battery. The little ground is hooked up, I went back over that first. What do you mean by an extra amp wire? And run it all the way back to the battery? Shouldn't it be running back through the factory lower harness? I have the + lead ran from the battery to the front of the car to a Moroso distribution block and the lower harness tied in there, which is the same as on my other car. Could this be the problem? I've made extra sure that this distribution block is NOT grounding in anyway.

The battery should not JUST ground w/ the block, but the chassis too. Not sure how you have everything hooked up w/o pictures. I was probably really unclear about this, I ran a 4 gauge wire from the battery - terminal, all the way to the front of the car and tied it in with the main ground on the harness (where it would connect if the battery were still in the front of the car) along the way, I ran smaller arms off the 4 gauge to separate spots along the way, the first being around 4 inches from the battery and going directly to the frame. I've managed to keep all of them fairly short. (this is something that I've seen some of the Le Mans cars run)


msglngth and stuff

[brokeAs240sx]

Alternator bench test fine (though bench tests aren't always 100% determiner) + 12v w/ car on = something w/ your wiring/fuses/etc, not alternator.

The reason I said run a pos wire from the amp -> battery is to bypass/eliminate whatever potential problems there are in your relocation/wiring/etc.

[holemilk00]

Alternator bench test fine (though bench tests aren't always 100% determiner) + 12v w/ car on = something w/ your wiring/fuses/etc, not alternator.

The reason I said run a pos wire from the amp -> battery is to bypass/eliminate whatever potential problems there are in your relocation/wiring/etc.


Ok will do, first thing in the morning. I'll keep you posted.

[supreme_1]

it still seems like somethings grounded, did you check all wires for cracks or arcing around your power wires/alt/starter?

what i usually do to check for shorts is: undo the negative battery terminal, and start pulling fuses one by one. it seems like you have a massive short, so if so when u touch the battery terminal to the battery it should give off a big spark. if thats the case pull fuses untill it doesnt spark as bad then look on that circuit. just make sure your doors are closed, if you have any accessory lights, make sure there off.

lastly but one of the stupidest things you can do, go around wires where you think may be bad or grounded and spray some water on it at night, if you see it arc then you know thats the prob