NEW BATTERY NEW ALTERNATOR STILL NOTHING

Is it turning over - or is it just dead silent?

its just dead silent right now, it turns over when i jump start it.but the battery to me it seems isnt staying charged, when i changed the battery a week ago it had some pretty bad corrosion around the terminal.

a couple questions.

year, make, and model would help me better answer you without involving my psychic abilities...

do you have a voltmeter?

are you testing for voltage at all, or just replacing stuff willy-nilly till you fix it?

Did you clean the terminal heads and the connectors - with a wire brush and baking soda/water solution. There must be a good contact there, or you won't get "juice'

yeah that would help you huh, the year is a 99 ford mustang, v6. no i dont have a voltmeter, but i did take the battery out before replacing the alternator and brought it to autozone and they said the battery was fine. No i didnt clean them, but i did change the terminals after noticing the corosion on the old ones.

a voltmeter is the next step. (you can usually purchase a decent one for $20 or so, or borrow one)

when the car is running the alternator should put out in excess of 12 volts (usually around 14)

I would charge the battery to full capacity off of the car, then put it in and measure the voltage when you start it. (the battery should not drop below 9v or so while cranking and then return to 12+)

and clean terminals are necessary.

also a word about the current state of the auto parts business...

just because it is new, does not mean it works.

I am running about a 30% return rate on new parts out of the box, and much worse that that on batteries from Wally-world. (4 0f 5 bad in less than 90 days, customer provided. I don't buy mine there)

ill try and clean the terminals again, but other then that, i just dont understand what it would be.

i got you, so my alternator could be bad just because i bought it new or my battery also, i mean i brought back the new battery and what they used to test it said it was good.

I can't answer you much further without voltage readings to guide me.

the solenoid is starter mounted, but I am listing a starter relay in the mix.

a weak starter can cause what you describe, assuming your battery is truly good.

(if they did not charge it to full and load test it, they just shined you on)

Your bad alternator could have drawn down the battery over the last week, too. Make sure it's got a good charge.

a few obviouse checks.
Is the battery connected correctly Positive lead to positive terminal.
red to red, black to black. (I hope its the same for the US as AU.)

Do the headlights lights turn on (and stay on for a few minutes) when the car won't start? is the light good quality (strong or weak) does it fade after a few minutes?
This will prove the battery is holding charge or not.

Is any part of the wiring bare or possibly touching the body work of the vehical?

Are ALL connections solid? especially any extra wiring like driving lights, car stereo etc directly connected into the battery or its main wiring loom? check these thouroughly.