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2G Low Voltage, The Electrical Illiad

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dudeX

10+ Year Contributor
126
12
Jun 14, 2011
Surprise, Arizona
This all started a couple of years back. First thing was the typical 3 lights that illuminate to tell you the alternator is dying. I had an oem alternator at the time and replaced it with an oreilys one, and yes I know those suck. Anyways it was like clockwork, in about a month or 2 the voltage would start to waver badly starting as a solid line on ecmlink and eventually looking like a saw blade bouncing between 13v and some times as high at 16v. I could hear my fuel pump wavering with the surges so I replaced it with a new walbro just in case it was the pump. I went thru 7 of these alternators and each died the same way. Due to the downpipe being nearby I assumed from what I saw and read that the regulators were getting murdered by the heat. I found an alternator reman shop here that my other DSM buddy used and his alt has been good for years. Car was at 13.8 to 14.1 immediately after the putting the alt in. After driving with it for a day my voltage is still stable but I'm getting 11.3v with the car on. About 12v with it off. I also replaced the 2 wires from the alt to the battery with thicker better wires as I thought I might've had a short somewhere. Car starts and drives fine and has no noticeable issues other than breaking up under throttle due to weak spark I assume. No idea where to go with this. I looked at the battery and it seems swollen and had a small amount of grey gritty looking gel around the covers that lead into the battery. I'm going to see if I can warranty it tomorrow and see if that helps. I've heard the ECU could be the issue but it was refreshed by ecmlink guys about 2 years ago as well, not to say it is good. I just don't know what to do and I can't drive my car like this. Anyone with experience dealing with something like this would be appreciated. The fuses were alll good as well, I checked the big 100a one and the similar ones and they are all good. Help!
 
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Sounds like you're battery might be the culprit. If it's sulphated or bloated, likely-hood is the electrolyte mixture is off and the battery can't maintain a normal charge, so the alternator was trying to work overtime to fix it, causing you to go through several and killing them.

Get the battery checked and if needed, replace it.
 
I'm on my way to take the battery in right now to have them test it. I know there tester doesn't really count for much but I stop by AutoZone 1st and they confirm that the battery is bad. Hopefully Firestone warranty this thing for me. I feel like I might have been a victim of the vicious alternator and battery life and death cycle. Hopefully after swapping out the battery I'll have a solid charging system

Got the battery warranty out. Went to hook it up and instantaneously I was at 11.8 volts with the car running according to my radar detector and turbo timer. The battery is 12.4v off, 12.1v started measured at the battery. Alternator is new but may have failed again in short order. I also don't have the lower heatshield but my exhaust is not stock so there's nowhere to bolt one anyways. No idea what is going on here.

Just swapped out the generator relay which I found out is located near the stock boost control solenoid location. No change, didn't even know that part existed until a couple hours ago.
 
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The generator relay doesn't deal with that exact scenario, there was a recent thread about it...

As for the battery voltage, sounds like you may want to get the alternator checked again and put the battery on a charger to keep it topped up.

Also make sure your alternator harness isn't all effed up from power steering fluid, heat and movement. The wires in the connector can become brittle and break, or lose sheething and become corroded.
 
I will also add if you do have to replace alternator there is one for a non turbo galant with auto trans as I recall that’s a direct bolt on for a 2g and puts out a extra 15 amps. For some reason 94 with 2.4 engine sticks in my head but has been a few years.
 
I took the alternator back to the remanufactured to have them test it then I was told that the alternator was not charging at all, he suspected the regulator was destroyed. Luckily I'm getting it warrantied out. I wonder if there can be any issues with my ECU that contribute to the alternators dying. I should be getting a new alternator tomorrow and with that I will have a brand new battery in a new remanufactured alternator remanufactured alternator. I just hope there's not some other underlying issue that keeps contributing to this electrical failure I'm experiencing. Anybody with experience similar to this please chime in, I could really use the help.
 
I doubt your ECU has much to do with the alternator failing.

The 2g style mitsu alternators are subpar overall and the way they ECU applies a duty cycle to the regulator to reduce alternator output to reduce engine loading is a really poor way to address engine loading.

I run a galant 90amp alternator in my 2g and it's really been no better than the oem 75amp, when the A/C turns on the ecu kills alternator output to reduce engine load then ramps it back up which leads to the lights dimming and then recovering as the ecu ramps alternator output back up.

The biggest headache is the ECU and it's intervention to reduce engine load, wish it was a programmable function.

The alternator relay as it's called doesn't really do anything functional to charging but functions to turn on the charge light on the cluster in the event of no alternator output if I recall correctly.
 
That's good info, thanks. So I have a good battery and a good alternator now. Rebuilder told me the old one appeared black inside. I'm wondering if I have an exhaust leak pointed straight at my alternator now. I'll investigate that and fix what I find if anything.

One thing I am interested in doing is making a heatshield for my alternator. Can anyone suggest a material that would actually reflect or do anything really to keep the insane heat away from my alternator? Not treating this as the cause but I may have many vectors and I'm tryna eliminate them as I find them. Thank you.
 
No comment on the alternator shield but wondering if you have a steering pump leakage, the steering fluid will kill an alternator if it has cheap internal parts.

Make sure there is no leaks dripping to the alternator.

I replace the alternator 4 times in a month, it was a lifetime warranty from the auto parts, after the fourth alternator I replace it with a used (from a junkyard) OEM alternator and never had a problem for a couple of years.

They always telling me I had a short somewhere and they were telling me the warranty might no going to cover in the future.
 
I took the alternator back to the remanufactured to have them test it then I was told that the alternator was not charging at all, he suspected the regulator was destroyed. Luckily I'm getting it warrantied out. I wonder if there can be any issues with my ECU that contribute to the alternators dying. I should be getting a new alternator tomorrow and with that I will have a brand new battery in a new remanufactured alternator remanufactured alternator. I just hope there's not some other underlying issue that keeps contributing to this electrical failure I'm experiencing. Anybody with experience similar to this please chime in, I could really use the help.
I’m having same issues. Have u changed fuse links and fuselink wires yet??
 
I’m thinking I may go with high volt alternator. But I’ve replaced my three times in last year. Is ur battery bolted down?? If it slides around that does it too. I know that’s something super simple but mine wasn’t. Didn’t consider it. The fuse links going bad will do that and the wiring to them. Have u reset ecu after each change of alternator or the fuse links themselves. ? Or relays? I’m stumped with mine. And I have done everything U have plus the wiring. And more. Also could be brushes in voltage regulator on alternator but it’s more than alternator to buy unless u buy a rebuild kit for brush replacement in voltage regulator.
 
brushes in voltage regulator?
fuse links go bad?
thats just going to confuse people.

a battery that shit itself will cause havok for the charging system and i myself have had a regulator go bad and cause a 15v+ charging situation and boiled my battery years back..
 
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