Battery charging problem!!!!

[STLskater92]

Hello everyone, I am completely new to the DSM world and just bought my 92 Eclipse GST about 2 weeks ago. I bought it knowing that there was an electrical issue, but for 700 bucks, I couldn't pass up the car and its proven 280whp.

The issue:
The car appear to have a slow drain of power both while running and while sitting. The car will run great on a new/recharged battery for about 3 hours. I can shut it off, turn it on, run the piss outta it, and even blast the A/C while listening to the radio. But after that roughly 3 hour window, the car will lose oil pressure, sputter and die, and refuse to start. I have a new battery in tere and fully charged it started the car, but when I went out in the morning to start it, the car refused to start.

Things already replaced:
Altinator (tested good twice at 2 different Autozones)
Battery
All ground wires

Possible problems:
I think it could be a wire between the altinator and battery shorted or grounded for some strange reason.
An accessery could be grounded wrong in the car
There could be a short in the wiring.

I greatly appreciate any help and will provide any extra information that is requested.

I am excited to be a part of the DSM family and can't wait to get my GST out on the streets

 

[hypergenesis]

From the sound of it I think its a wire being grounded draining all the battery,

 

[luv2rallye]

http://www.dsmtuners.com/forums/art...-partial-short-battery-drain.html#post1496998

 

[FIBA M - EC17PSE]

Just because your alternator was tested good doesn't mean it works! I brought a brand new unit from mitsubishi and it charges fine until it warms up then stops charging! But my old unit now works??? And that charges up once hot so the alternator could still have a fault in it! So its tricky as 2 major electrics run the alt and both of them need to be checked and replaced before you can say the alternator is ok! Have you looked at the fused? Just in case one has melted and fused to the body? Check every part of that wire for small cracks and breaks in the circuit!

 

[STLskater92]

Thanks for all the quick repys!!! I'm gonna spend a few hours tonight trying to find a short. I replaced all the fuses and ground wiring the day after I bought the car so those are all good. I also replaced all the relays as 2 were melted!!!! I did notice my light on my boost guage doesn't work last night so I'm gonna take the dash off and go over all the after market wiring. (The original builder of the car liked to take shortcuts so I may need to do a full wiring overhaul haha) I'll reply later tonight with a solution or cry for more help hahaha

 

[97gst_spyder]

Have you checked the ALT Fuse in the engine bay? Mine blew and drained the battery, but ran ok until if fixed it.

 

[AWD Devious]

Do you have a system in you car? if you do and its not a good battery like a optima and also you need a capacitor. you might want to check in to that.

 

[steve]

I don't see any voltage measurements posted and that's the first thing you do with charging issues.

What's the battery voltage with everything off?
What's the battery voltage once the car starts?

 

[turbo98eclipse]

I don't see any voltage measurements posted and that's the first thing you do with charging issues.

What's the battery voltage with everything off?
What's the battery voltage once the car starts?

yupp-- thats what i was going to say... use a volt meter to test the alternator with the car running, if its 14.2-14.5 its most likely still good. anything under 14 means its shot.

you can test it at the battery (one probe on the +terminal and one on the -terminal) to test for connections between the alt and the battery, and also test it with the -terminal on the body (a nice ground point) and one on the alt itself to see if its pumping any juice out at all... that will help you narrow things down

 

[luv2rallye]

Battery and alt test: http://www.dsmtuners.com/forums/new...reeway-electrical-problems.html#post151165661

 

[STLskater92]

The car has a new alt. fuse and I have no system in it. I'm actually taking the dash out to look for a short or accidental ground now. The altinator tested good again at autozone but bad on the car??? I'm thinking all new wiring should fix this. I'll have to check the battery tomarrow, my volt tester is at a friends and he won't be home till tomarrow night.

 

[luv2rallye]

Auto stores (Autozone is the worst) are notorious for selling bad alts and their testers are worthless. The only real decent (also complete) alt test is at an alt/starter repair shop. Do the battery/alt test I provided to determine which if either is a problem.

 

[thumper_1151]

test the battery voltage running and then check for a draw. it could be somthing as simple as a radio drawing power with the key off.

 

[Kittaping]

I took my alt to autozone and they said it was fine. Then took to advance auto and it was actually bad. Advance auto has a better machine to test on (qt least where I am) my GsT was doing the same thing but it was because my FAL fans were hard wired and they drained my battery and the alt wasn't strong enough to power everything so I blew both battery and alt. Oops

 

[STLskater92]

May have found the problem!!! The guy who built the car didn't ground the guage lights for the pillar. I'm gonna redo the ground for all the guages and try and start the car again tomarrow. If not, I'll take the altinator to Advanced Auto and see what they say about the altinator. Thanks again everyone!! All this has been a huge help!!!! (I'm actually finding little things to fix along the way because of it haha) I'll respond tomarrow if I've come to a solution.

 

[kxfreak125]

My car has been having the same problem. I just installed a brand new 90 amp alternator from advance auto thinking that would help and nothing. I dont have a stereo either, this whole issue is really starting to bug me because I really like this car.

 

[STLskater92]

Big update to this problem!!! I completely removed the dash and double checked all wiring. I fixed anything that was bad or connected wrong. Put everything back together and started it up, but to no avail, the problem consisted. I managed to get it to autozone (no clue how ) and the altinator tested good off the car, but once back on the car, it was charging like 22amps and less than 11 volts. The guy says I should replace my altinator wiring but I'm not 100% sure if that would help the draining problem when the car is off. Any input to my new situation??

 

[turbo98eclipse]

Did you do what I told you? It can significantly narrow the problem down in under a minute...

If they test it in the car, at the battery, and its 11v... then its most likely a bad wire between the alt and the battery (as in the car is running straight battery). Did you check those wires yet?

Do what I told you a few days ago and it will point you in the right direction. I'm a mechanical engineer and have several ASEs including electrical diag... trust me.

 

[STLskater92]

Ok, I have an altinator wiring harness on order but am wondering if that will fix the battery drain as well. I know it will fix the charging issue, but will it fix the issue of the battery draining when the car is off?

 

[Kittaping]

It could be the diode in the alternator. Your alternator will test good but the diode will keep the battery pushing power to the alternator even when the car is off. I had that problem in a car of mine. You can disassemble to alternator to check the diodes and replace them separately instead of buying an entire new unit. I'm telling you take that alternator to advance! Lol or better yet napa if you have one.

 

[GRAVEDIGGER]

Ok, I have an altinator wiring harness on order but am wondering if that will fix the battery drain as well. I know it will fix the charging issue, but will it fix the issue of the battery draining when the car is off?

You know your not getting a good charge to the battery, so fix that problem first and then move on to a parasitic drain issue if you have to go there.

You need to have 13.5-14.8volts coming from the alternator and going back to the battery. If you don't have that kind of voltage at the battery, make sure you have it at the back of the alternator. If you have good voltage at the back of the alternator, but not at the battery your wire is bad going to the battery.

So, get good voltage output within the specified range to the battery and see what happens. Good luck!

 

[STLskater92]

So i tested the battery and altinator. They both pulled 12v while the car was running. About 5 minutes later I checked and they both were at 11.8v. With the car off, I tested the battery and altinator and they both pulled 11.8v but litterly 15 seconds later the guages read 11.5v. So the wiring between the altinator and battery allows flow of electricity. Could there still be a short or ground? I'm testing off the little post at the bottem of the altinator BTW.

 

[turbo98eclipse]

So i tested the battery and altinator. They both pulled 12v while the car was running. About 5 minutes later I checked and they both were at 11.8v. With the car off, I tested the battery and altinator and they both pulled 11.8v but litterly 15 seconds later the guages read 11.5v. So the wiring between the altinator and battery allows flow of electricity. Could there still be a short or ground? I'm testing off the little post at the bottem of the altinator <<<ALTERNATOR!!!BTW.

if they are both around 12v then sounds like its running straight battery. 99% of the time its your alternator

and no if youre checking directly at the alternator then it cant be a short

 

[steve]

If your seeing less than 13.6v at the alternator stud it's not charging.
Your voltage keeps dropping because your running the car off the battery.

Look at the two wire connector going to the alternator, one is the sense line and the other the field for bootstrapping the alternator. It's where the alternator draws power from when you first start spinning it until it making enough power to self-energise.

 

[STLskater92]

Well, I do believe I have the problem fixed. I got a new alternator and all new fuses for the fuse box in the engine bay. The alternator now charges the car at roughly 13.9v. It ran for over 2 hours straight today and started up 5 hours after putting the new alternator on. Only thing left to do is see if it starts up tomorrow after sitting off for over 7 hours. I appreciate all the help everyone!!! I'll put the thread as resolved tomorrow if everything fires up.