HELP, alternator problem

My Daughter has a 1990 Honda Civic with an intermittent charging problem (it
seems)

Her car will be fine one minute, then she'll stop at a light, everything
will go dim and slow down like the engine was running on the battery and it
was dying, when she rev's it up, it all comes back to life, she was also
having trouble starting it occasionally, it turned over slowly and had to be
jump started a couple of times

Thinking the alternator was toast, I brought it home, disconnected the
battery cables while the car was still running and the engine still ran ok
off the alternator

She bought a brand new battery for it and all was ok for a couple of days,
then it started acting up again, everything dimming at a stop light until
she revved it up and then wouldn't start when she parked it.

Is there more than just the alternator in there like a voltage regulator or
something that could be the problem

One thing she had installed in the last few months is a car alarm, she had
it installed professionally but I think there could be a short somewhere in
there because when she is trying to jump start it, the alarm activates or
arms itself and goes off

Any suggestions?

Thanks for your help in advance

Brian

 

Hi,
Car alarm draws current in stand-by all the time but not to a point of
draining battery to dead. I'd start with checking all the cable
connections. Sounds like loose cable somewhere. Two main battery cables
and smaller wires for regulator signal, etc. When car is shut off, you
can measure current draw from battery. If you don't have a multi meter
handy, just put a 12V small bulb in series with positive battery cable.
If it lights up bright, something is drawing too much current. If alarm
is suspected, remove the fuse for the alarm and see if it makes
difference. Or you have worn out brushes on the alternator.
Tony

 

-----------------------
Brian,

Too sleepy to offer a solution, but here's an important tip: Never
disconnect the battery leads while the car is running. Too much
expensive stuff to fry when the voltage soars. This point may even be
mentioned in your owner's manual.

'Curly'

-----------------------

 

You could have a bad ELD, which would keep the alternator from sensing the
electrical load properly. Have you had a problem with the batter not
holding a char also?

 

Found the problem...

It was the 60 amp battery fuse in the fuse box, the previous owner must have
been tinkering with it because it was very loose and the contacts bent to
the point where the contact to the fuse was very sub par, Went to Honda, got
a new fuse (new contacts included) and now works like a charm

Thanks for all your help

Brian