petersonm

Hi everybody, so i have a weird problem that has been going on for a while (like a year, no joke).. hopefully someone can help because i am out of ideas.

So my battery went dead when I driving a while back and i put a new alternator in. I also replaced the battery around the same time.

Everything seemed ok right away but i have been struggling with it since. I have had my car die while driving about a dozen times now. The weird thing is, i can jump start it, check it with a multimeter, and its charging. Ill keep driving it (sometimes a week, sometimes months) and then it will happen again.

It has been into a couple shops, one couldn't find anything wrong with it, the other said the computer was bad. I replaced the computer (the one behind the glove box) and i still have the same problems.

Does anyone know where the voltage regulator is? Is it part of the alternator or is it somewhere else. Is it possible i have a bad alternator/voltage regulator?

Just over the weekend i had it die on me, when i jump started it i checked the battery with a multimeter and it was jumping around from 0-14 volts (yeah, weird, i know). I then shut off my car, let it charge for a little bit with jumper cables, started it and everything was fine again. I then drove it 40 miles home with no problems. (grrr) and then another 45 miles today with no problems.

I want to say it happens the majority of the time while it is damp or rainy out if that helps at all.

Also when I drive at night, when it is charging "properly", I have very noticeable dim in my headlights (i can even hear my blower fan slow down and speed up) from idle to about 2,500 rpm. Checking it with a multimeter confirms this, ~11.5-12v idle to 2500, ~13.7-14 2500+.

any suggestions appreciated. thanks

HornstarBU

iTrader: (7)

I think my voltage is like 13.6 constantly, idle or cruise, so you might have a couple issues. Check the belts, make sure the alternator one is tight, check the plug on the alternator to see if it's loose or anything, make sure the wires aren't burnt looking or touching anything hot.

My bet, it's not the computer, but that's obvious since you swapped it, or anything related to tune. It's gotta be the alternator isn't supplying the power or the battery isn't accepting the charge, so a short somewhere would be my guess if the belt is tight. Check all the grounds, and use the manual to find em if you can't. The manual is in one of these forum posts somewhere, I can find it later if I get a chance.

lil' jeff

iTrader: (5)

the regulator is part of the alternator. just cause the alternator is new it could still be bad. you might have a wiring problem,bad ground. i would run a second ground from the battery to the frame and see what happens,but sounds like a bad alternator to me.

petersonm

thanks for the replies.

The belt is tight, i put some belt dressing on it recently too.

I pulled the plug on the alternator and put some dielectric grease on it, the wires all seemed ok.

I have suspected that i might have a bad ground somewhere because it seems like my radio doesn't come in as good as it used to. I'm not sure if that has to do directly with grounding issues, but it seems like a clue to some sort of wiring problem. I did have a mouse running around in my car for a few days a long time ago...(i trapped that little bastard REAL quick.) haha

I am thinking that I'm going to swap the alternator and check the grounds. I really hope that will fix it.

If anyone else has any suggests, please let me know.

thanks again.

HornstarBU

iTrader: (7)

autoparts store can also test the alternator

petersonm

can someone verify what alternator should be in my car? 2003 mitsubishi lancer, oz rally, 16v sohc. I looked up the part number of the alternator I got from Napa on their website, and it shows that it is for a 2002, and its a 85amp. If i search for a 2003, I get a different alternator, which is a 90amp. The "alternator clock position" is different between the 2 as well. I am starting to think all my problems have been from having the wrong alternator in my car in the first place. any helps appreciated. thanks.

mitsuozboi

iTrader: (18)

02-03 Lancers are identical so they shouldnt be different. But maybe they gave you the wrong one.

03lances

iTrader: (14)

Definitely sounds like the reg in the alternator is bad. Its all in one no separate regulator. If you can find a way to test your voltage right from the alternator plug this will tell you if your alternator is bad or if you have a wiring issue somewhere inbetween.