Need a little help diagnosing weird charging issue

[Jimmah]

My wife's 99 Escort wagon (2L, auto, 2 bolt alt.) has been very cranky with charging issues these past few days. Symptoms are: usually starts fine (sometimes it is hard to start) and drives fine, but lights have been going dim this past week intermittently up until last night when the battery light came on and the engine got VERY displeased and died after a short while.

Fast forward an hour later after my father arrived and boosted it, died right away after cables were removed (at this point I'm thinking alt or wire to battery is bad) so we re-boost and let his car charge our battery for a while. On the way home it runs flat and died again, did the charging thing again and eventually got it home.

This morning I get it started (no problems starting) and let it run while watching the voltage with my multimeter, didn't drop below 14v for a good long time and the engine was labouring while charging the battery. Car got warm and the alt stops charging, battery slowly goes flat over the next 20 mins. Only would charge a little when I gave it a blip (nothing higher than 13.3v though, hovered around 12.2-129v).

Past issues it has had were things like battery dieing (less than 2 years ago) and was replaced, corrosion on the pos pole (enough to stop it dead while at a gas station of all places).

My thoughts are it's a possessed alternator that only likes the cold, or the control module (I think that's what it is) is going awry.

Anyone have thoughts on what I should do or what the problematic part would be?

Thanks for any help

 

[woodie1]

It is probably a diode in the alternator that fails after it reaches a certain temperature.

 

[techs]

An alternator sized alternator?

Oops. Wrong forum.

 

[Vette73]

Yep something in the Alt is going bad. It might last another day or month, but better to replace now then be stuck on the side of the road.


But also check the wires at trhe Alt to make sure they are good. I have seen some fords, older ones mostly, burn through the wiring at the Alt.

 

[dud]

OP,

First, real men don't let their wives drive an Escort wagon.

Secondly, yes the alt is probably going bad. It sounds very much like the same problem that I've had MANY times ... a charging system malfunction.

Solution? Easy. If you can drive it take it down to your nearest auto parts store and have then check the output voltage from the alt ( a previous poster noted the diode going bad). They have the diagnostic tools to do so. They should be able to tell you within minutes. If the alt is going bad (probably is) just buy a lifetime replacement (probably a refurbed) alt at the store. It should be relatively easy to replace.

Remember, if the alt is going bad and not charging the battery correctly AND you battery is running dead then you should consider also replacing the battery as well. Auto batteries are not meant to be discharged to that low of a level.

Good luck ...

 

[Jimmah]

Fixed it up this morning. Turned out to be a wasted brush (had broken off past the wear hole), rebuilt the unit with the rebuild kit and put 'er back in, started charging immediately. Very pleased.

It's my wife's car given to her by her parents (who pay for the insurance also for some reason), really can't argue with that, even if it is not terribly pleasing to the eye.