battery wont hold charge

[nksmx-3]

well I replaced the alternator 2 times now and after the second time I had it checked imeaditly, and it was only putting out 11 amps, as to 55 like it should.I dont have anythig special like an amp or major sound system. I do have neons that are wired to the dome light so they come on only when the doors are open. please I need help, and fast. oh yeah, the other day I was driving and my RPM gauge was acting funny, when I tapped the brake pedal It droped down to 0 RPM's, and it fluctuated up and down when I put on my turn signal.

[Ogimoj]

Your tach dropping like that is an indication of low voltage in your electrical system (the extra load of the brake lights dropped you already dying battery voltage too low to power the instrument cluster. This implies that the alternator isn't supplying the power like it should. Check that the power cable and the regulator connector are both well connected. The current draw on the alternator depends on load at the time of testing, so 11 amps doesn't really sound abnoraml - depending on what components were turned on at the time. The motor will run for quite a while without an alternator (I've been suprised), but your tach failing is an indication of impending discharge. They always say to be sure to fully charge a battery prior to replacing the alternator to prevent undue load on your new alternator.
Try this:
Start the engine. Remove the negative cable from your battery. If the engine dies your alternator is no good or not properly connected or not being turned by the belt. If the engine continues to run normally, then the alternator is most likely fine, but you may wish to have your battery load tested (most auto-parts stores will do it for free).

[nksmx-3]

I just went out and bought a new battery, and the charge light in side is still flashing when I tap the brake pedal. Ill try now you test but, the newset alternator was replaced only 2 days ago and it was tested right befor I bought it. if it isnt the alternator or the battery, then what is my prob? oh yeah, all the connections look clen to me.

[nksmx-3]

ok I tried your test and the engine stalled, so what now, what happens when an undue load is put on a new alternator? could it crap it out? cause I dont want to take the alternator back and have them say it is fine. could it be bad wiring? all my conections look clean, so I am totaly lost on this whole thing. should I take it to a shop on monday. thanks

[airjordon_09]

ok bro, i didnt bother reading his posts no offence to him or anyone, im just very lazy right now :p but if anyone knows about electrical problems as many on this site know, if its electrical, it has gone wrong with my car. <p>get a meter check to see if your car is draining even when the car is off, it sounds like your problem is that your serpintine belt is either too loose or just ****ed, take your car to an electrical place, not a regular mechanic, <p>
peace

[Ogimoj]

If the car stalls when you remove the battery cable, then the alternator isn't prividing power to the engine. Putting an alternator on a competely dead battery can damage the alternator (from what I've read - never seen it myself). Sometimes the alternator comes with a sheet attached that says if you do that, the warranty is void on the alternator. The only other things left to check (that I can think of) besides the alternator are:
check continuity between the alternator power connection and battery (unlikely that it's a broken cable, though)
check for good belt tension
otherwise, you got a bad alternator. If you happened to have got your alternator from autozone, then I almost gaurantee that is the problem - they're notorious for bad alternators and starters.

[nksmx-3]

well I took it into the shop yesterday, it was a loose bolt in the fuse box, the guy at the shop said that it should never come loose on the life of the car unless someone goes in there and purposly loosens it, well I can think of is mazda, cause they just replaced my seatbelt, and after that my first alternator went, and then all the probs started to happen. well thanks for all the replies on this guys.