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Alternator wiring question

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Millhouse118

Probationary Member
11
0
May 10, 2010
Greenup, Illinois
Hey everyone, I have a 1990 Eclipse GST rally car. Im having a small problem with the alternator not charging properly. I havnt tested it because it worked before i had to some wire repair to the starter. Not ruling it out that it went out, just stating that it would be odd for it to go out all of a sudden.

Here is where it gets really interesting, i have a main power switch for obvious racing reasons. Basically i can drive the car and after awhile it starts losing power running like doggy doo and eventually dies. This is all based on how hard you drive it etc. (harder driving uses more power) but once it dies and sets for a few mins the battery gains enough juice to start and run again. So im fairly certain its not a fuse i check the main alt. fuse it appears to be ok, there is a relay labeled alt as well i believe in the same fuse box?

When i worked on the wiring it was due to the little slip on terminal on the starter solenoid pigtail broke off. I completely removed the battery, the small wiring harness that the starter wire is attached to and soldered a new wire and terminal on. I thought i got all wires hooked back up correctly but now am starting to second guess myself. Is there a plug in or wire in that harness i might have switched up or forgot? I had a few grounds un done from the fire wall and neg. battery cable.

I have one of the repair manuals but the wiring diagrams dont help much in the way of alternator wiring. Another thing with that main power cut off wired in, the wiring is a little goofy under the hood.

Any help in sorting this issue out is greatly appreciated. Thanks everyone.
Millsap Motorsports Rally Team

If anyone has any help it is greatly appreciated, im shooting for making the Perryville, Missouri rally the 27th of October so the sooner i get it sorted out the better.
 
Does the starter work correctly each time you go to start it? If so i pretty certain your issue does not have anything to do with your starter repair as you have the solenoid wire, the cable from the + terminal straight to the starter and the ground from the starter that normally grounds the bolt into the transmission.

What strikes me as odd is that your car dies, it sits, and then can start and drive again for a certain amount of time and then die again? Is there anyway you can temporarily disconnect your main switch and see if that is causing any issues?

The battery is not going to just gain a charge when the car dies. The car has to be running for the alternator to charge the battery. The battery will not just charge itself to start your car. I also dont see that the harder you drive the more "power" or electricity you use. If anything it sounds like a fusebox / your modified wiring in the car. The battery would not be able to start the car after driving if the alternator was not charging it. Is the battery light illuminated on the dash? That normally will be illuminated if there is a battery / alternator issue while driving.

I am probing hard into my brain thinking what might help you at this point but again it does not sound like an alternator issue rather a fusebox / wiring issue.
 
Your alt is not charging the battery. If both the alt relay and the dash charge light malfunction the alt won't put out. The alt relay is a backup for a burned out charge light but sometimes the relay fails. Check the light first however. If it doesn't go on when you first turn the key to on, that's a problem.
 
Thanks for the replys. I truely appreciate any help. I also thought it was weird that after sitting it will start back up. As stated before batteries don't magically become charged. I don't remember seeing a dash light on when it occurred. I was driving down the road and it wouldn't rev above 2500-3000 it almost sounded like anti-lag the way it ran then I pulled in y driveway and it let off of the accelerator and it died. Won't crank over at all. Let it sit for 15-20 mins fires up and runs fine. It's stumping me. Thanks again guys.
 
Batteries do something called "reclaiming". Thats why it will start after 15 minutes. The voltage actually slowly increases while a battery isnt in use, back to its normal 12v. This wont happen much longer though, as eventually you will destroy the battery by doing this and letting the alternator under charge it. Check voltage at the battery at idle. Should be a min of 13.7 to 14.4. If its low, check it at the alternator post. If they differ, then wiring problem, if not, alternator is shot.
 
Ok well im not ruling out the alternator is bad, it just was an overnight thing if did go bad. Worked just fine coming home one night, then i noticed the broken starter wire. Thats when i took that mini starter harness off to repair it properly. Now when i drive at night with the lights on and hit the brakes the lights dim for a split second then come back to normal or so it seems. When i first stumbled on the run problem was coming home from work one day. I drove the car to work for the guy building the new cage to see what he was working with. Well i first noticed it when my 9am break came. I hopped in to run up the gas station real quick like and to take a guy for a ride. I romped on it pretty good for about a half mile to the gas station. I let it run for about 30 secs before shutting it off to let the turbo cool. When coming back out to leave, the car started a little hard, sort of slow turning over. I thought it was kind of weird but thought maybe i was just imagining things.

Ok so now its 4:30pm time to go home. Hop in the car starts right up, on the way home i really get on it (a 25 minute drive) about 5 miles from home i lay it on the floor all the way to the rev limiter just testing some handling concerns. Then about 2 miles away i take a turn and try and get on it, it wont rev over 6000rpm when it hits 6000 it spits and sputters loses power it feels like. I start to get a little worried, i kept trying to rev it the rest of the way home it just keeps getting worse. By the time i pull in my driveway it wont rev over 2500 doing the same thing spitting sputtering almost a backfire antilag sound. As soon as i pull in the driveway and let off the gas to push in the clutch the car dies. I really start to get irritated. Try and start the car nothing. No relay clicks no fuel pump prime, nothing. Sit for 15-20 mins starts right up like a champ. I didnt let it run real long out of frustration. This is bad of me but i dont remember if there was a light on. To my vague memory there wasnt a light on at the time. But i do know the light comes on when starting the car to answer the previous question. So there is the whole run down of sorts. Really mind boggling at this point. I have the battery and tray back out trying to see if i missed something and nothing really jumps out. Thanks again for all of your answers already. I am shooting for the Perryville Missouri Rally October 27th. Between this problem and the new cage install im pushed for time already. So any help at all is truely appreciated guys.
 
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batteries do something called "reclaiming". Thats why it will start after 15 minutes. The voltage actually slowly increases while a battery isnt in use, back to its normal 12v. This wont happen much longer though, as eventually you will destroy the battery by doing this and letting the alternator under charge it. Check voltage at the battery at idle. Should be a min of 13.7 to 14.4. If its low, check it at the alternator post. If they differ, then wiring problem, if not, alternator is shot.
^^+1

Do alt/battery test: http://www.dsmtuners.com/forums/new...reeway-electrical-problems.html#post151165661
 
Ok well i hate to beat a dead horse but since the car is at the welding shop getting the new cage i have been doing research, alot of my problems sound like it is a bad voltage regulator. Does this sound correct? I will for sure do an alt. test when the car gets back but, at this point im leaning towards the voltage regulator. Thanks again for the help.
 
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