she has a 95 protege 1.8 automatic
it was having a problem of running down the battery
i changed the battery
it happened again so i changed the alternator
car was performing the same, it will idle forever but when you start driving it with ascesories on (rear defrost, heater/defog, lights, and wipers) all the aforementioned seem to bog down and i lost the speedo and tach
i cut the positive terminal off cleaned it up and sweat it back on
on the way to work this morning all was fine untill i reached about ten miles from the house with all ascesories on and the bogging down started again, and again losing the speedo and tach
i had to drive home at 6 this morning with everything off and made it by putting the car in neutral at stops because the break lights were bogging it down.
this afternoon i did a ground test for the block and it checked out ok
i also drove 2 miles to the parts store to get a diagnostic check, no dice, they can only test to 96, anyway no problems it operated fine
so with no ascesories on the car seems to function fine however i haven't tried a longer distance run
so i hope someone can help me out because i'm about to run this car into a tree

 

Sounds like a poor ground connection form batt negative, or the alternator itself. If the alternator output is 13-14.5 volts, then it will charge the battery. Can you check the battery positive to groundwith a voltmeter? Look for 13-14 volts with engine running. Also, check the battery voltage with engine off. No accessories on. Should be 12 volts to ground. If the two voltages I described are there, then you are encountering an intermittant ground that shows up when you are on the road.
First, disconnect the negative ground cable at the engine block, or wherever it bolts to the car. Sand it, and clean the surface on the engine where it makes contact.

 

One more thing: a battery with a shorted cell would cause these problems, check the voltage on the battery w. engine off, and, with engine running. Also, check to see that the battery is large enough to handle all the loads running at the same time. Sometimes, you'll get a battery that is undersized for the application.