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Hi everybody, I need a little help, here is my problem, can you please help me out?

I am having problems with power in my car, I have replaced my starter, the alternator has been tested and is fine, replaced my battery terminals and the battery and still no luck. Here is what is happening.... The car keeps dying on me, I charge my battery and 2 hours later it dies, it slowly shuts down losing power first my lights dim then my gages shut off and then everything shuts off and it is dead... I have tried everything I can think of, so please help me out... Your response as soon as possible would be appreciated as I am taking it to a mechanic tomorrow and I'm sure you know electrical problems can be tough to figure out and dont really want to spend like 500 bucks for someone to figure it out... Thanks in advance...

I did a search for similar problems and found a couple suggestions about a bad ground if thi is possible can someone answer two things
a)how would a bad ground cause a problem like this?
b)where are some spots where the bad ground could be so I could suggest it to my mechanic to cut down costs, or just check it myself?

Thanks again

bad ground equals short
bad short equals power loss

Originally posted by tical:
bad ground equals short
bad short equals power loss

That's not the case. A short is a very low or zero resistance between parts of a circuit which should have a high or infinite resistance between them, i.e. they should be insulated from each other.

A bad ground is a high resistance between the negative terminal of a service and the steelwork of the car, which is used as the return path; this should be a very low resistance, or zero. So a bad ground will result in less current flowing than should. In your case, if there is a bad ground between the alternator negative terminal and the battery negative terminal, this could explain why the battery does not appear to be getting charged by the alternator.

<small>[ December 09, 2003, 03:44 AM: Message edited by: IanL ]</small>

Thanks guys

There is an obviously short between the Alternator and the Battery. The battery is running the car and when it looses its charge you loose your mode of transportation.

How did they test the Alternator? In the car or on a bench?

they test the alternator while in your car. ive had it done many times...

just puttin in my 2 cents, thanx for settin it straight...

Testing the alternator may not reveal the fault. The alternator could be functioning well. If the battery has a high resistance connection on its NEGATIVE (e.g. a bad ground), not a short, the problem will give the symptoms described.

Another possibility, which does include a short (i.e. bad insulation) is if the battery POSITIVE has a low resistance to ground. This could include poor insulation across the battery terminals, which can happen if the casing has a hairline crack which fills up with crud. The charge leaks away faster than the alternator can put it in.

when u say hairline crack in the casing do u mean on the the terminals that go on the battery, if so i know it isnt that i just changed them, and then bad ground on the negative wire doesnt seem right as i just cleaned its ground location unless the whole wire is toast....

Remove the battery connection to the alternator (the cable that bolts onto the back of the alternator) and check for corrosion underneath it. I just worked on a Ford that had the exact same problem you described (alternator tests fine, battery is good) and it wasnt until the alternator was removed that we found the corrosion. It doesnt take much corrosion to mess up a good connection.

ok it looks like we've traced the problem back to the alternator and it appears that some oil leaked into at some point and has screwed either the regulator or the wires... so now i need to take out it rebuild or just just clean it. Can you guys help with how to get to the alternator it doesnt seem to be in the easiest spot haha from what I see your two choices are lift the enigine or take off your front end... a big ain in the *** either way can someone help with an easier way , if there is one?

sounds like it is definitely an alternator problem.

Also...it might be worth tracing the connection from the alternator all the way to the battery. On my Protege, this wire melted near the alternator eliminating the connection. I had to cut out a chunk of it and replace it with some new wire.

Also check grounds to alternator and battery, it won't function properly without em.