Subaru Forester Owners Forum banner
1 - 5 of 5 Posts

·
Registered
98 Forester 2.5
Joined
·
3 Posts
Discussion Starter · #1 ·
So I have a 1998 forester, bought it with 120,000 miles for a grand, and drove like a dream for the first few months of my ownership. the alternator HAS BEEN REPLACED by the previous owner with a NAPA replacement. after a while, bulbs started to burn out, such as the shift indicator and dome light bulbs, headlight sockets melting and the such with a strong burning wire smell when kept in the garage. as I was troubleshooting this, my sister needed to borrow it as an emergency and drove it across town. on the way back, the abs light, brake light, and battery light came on, both the tach and speedo baselined, and the stereo shut off. she got it back home and I parked it. Assuming it was the alternator overcharging the system I purchased a new one (as I work at autozone) and installed it. car ran like a champ after the change, sitting at 14 volts charging. after about 5 minutes I put my multimeter on the battery terminals and saw it drop from 14 charging to 10-11 volts charging, also noticed the headlights dim significantly. Because of the battery being overcharged, I purchased a new one and this also gave way to no improvements. the only other thing I can think of is that the voltage regulator wires are shorting out somewhere.

any ideas? thanks for the help guys.
 

·
Registered
98 Forester 2.5
Joined
·
3 Posts
Discussion Starter · #3 ·
battery connected is 14.5ish for about 5 mins, and then everything hits the fan, and then its about 10.

anybody? anything? im surprised that this isnt a common problem...
 

·
Premium Member
2014 328i xDrive Wagon 8 spd Auto
Joined
·
1,975 Posts
Given the age of the vehicle, I'd be looking first at basic electrical grounds and connetions. So, tIme to go back to the basics, if you're comfortable doing this:

1) Check and re-do all the ground connections, i.e. battery ground, starter connections, any ground straps, etc. Also, any wire you can see that ties to chassis, clean and re-do the connection. It might not help, but I guarantee it won't hurt, especially in a ten year old vehicle.

2) Make sure the battery cables are perfect....good connections at battery, cables pliable, not brittle, etc.

3) Ditto the starter connections.

4) remove every single fuse you don't need to keep the car running, i.e. lights, radio, A/C, etc, until you've just enough left to start the car. Don't drive it anywhere like that, just start it.

5) recheck the battery voltage

6) while monitoring the battery voltage listen very closely and see if you can hear any relays at all clicking in when the voltage drops. It seems especially telling that things are fine then a few minutes in there seems to be an event that causes things to go down the tubes.

There's a couple of obvious things that will cause some of this....one is that the voltage regulator (built in to the alternator?) is putting out too much voltage. That'll shorten the life expectancy of the bulbs really fast, but contradicts what you're seeing at the battery unless the alternator's gone south.

Or, there's high resistance in the system, causing too much voltage drop across a connection, which in turn can make heat, which in turn can melt wires in an extreme case.

Or, there's a short in the system that's pulling down a lot of current. If you have access to a current shunt you could hook in series with the battery, it could prove most illuminating, i.e low current draw normally, then when the battery voltage drops you notice the thing's drawing a lot of amps.

Lots to try, sorry I can't be more specific.

Good luck and keep us posted.
 
1 - 5 of 5 Posts
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Top