ok all need some help here.
So here is the issue
Charge battery - car starts.. let it set over night and either very little power or none at all.

So lets discuss when it was first noticed.
Car was in the drive way with the gas tank dropped for a week waiting for my new fuel pump, got it put in went to start the car, and it had no power, charged battery and ran fine, has been a daily issue now having to charge it.

I have had both the battery and alternator checked, both check out good.
Also I disconnected my amp, and today it did the same thing.

Any help guys?

 

If it was fine before then that would lead me to belive something is faulty with the wiring for the fuel pump.
That's all your saying you worked on and didn't touch anything else right?
Check the pump is it staying on? Pinched wire or ground maybe on install?

See last line below for a quick check if it's the pump!

Patristics loads are hard to find.
Process for finding it
1) aquire a multimeter with a ammeter function and set it to amps( most are fused for only 10 amps)
2) disconnect the battery positive and connect the leads one to the battery and one to the positive cable
This allows current to flow and meter should show a current.
Donot turn car on or put key in to the ignition!!

3)start disconnecting things you might suspect (pulling one fuse at a time is a simple way to narrow it down)
Once you figure out which circut is drawing the current let me know and I can probably tell you what's all on it.

Each time checking the meter to see a big drop in current.(you would have to see a few amps on the meter I would think.

Note it will never go to zero the security stuff and some other thing draw a little current all the time!

But if you can't get a meter I would just pull your fuel pump fuse first and put it back in the morning to see if that's it!!!!

 

Is the car turning over at all, or just nothing at all when you turn the key. Interior lights? Give us some more details.

I had the same problem last winter. No power, car wont start. Interior lights and radio would work though. Jump car with cables, starts and runs fine, can even turn it off and on multiple times throughout the day and its fine. Leave it for a day or so and same problem. Pulled the battery and took it in to get checked. They said it was perfect. After a few more days of carrying cables with me I gave up and bought a new battery to try - problem solved!

 

So i got a reading of -2.26 and then pulled both fuel pump fueses and the reading stayed the same

 

so if I got out earlyer in the day, the dash lights will come on when i open the door and everything but the car won't start, may try to turn over halfway but thats it... if i go to try later in the day there is no dash lights and nothing happens the battery is dead.

 

Start here, there is no better way to narrow down the problem. /thread

 

removed my power windows fuse, and it droped to -0.15 and after replacing it went back to -2.x then back down to -0.15

 

ok. hmm. at this point i would suggest pulling the switches from the door, unplug one side at a time and see if it changes? i dont know who exactly these cars are wired, but youre on the right track for sure!

 

yeah it wasnt the power windows went back and checked it and it was back up again.

 

Found it.... it's my radio... pulled the fuse and it dropped down to -0.3

BLAH how sucky is that...so will just getting a new radio fix the problem?

 

Glad to see you figured it out,would of been more than the price of a new radio if you had to go to the dealer.

Just to let you know your getting a negative reading because the leads are backwards,no biggie though works both ways!

 

Do you have onstar? I know that **** is wired through the radio harness and such, dont know if it pulls a charge while the car is off (gps monitoring etc). I'm still going to say its a bad battery, just because of what happened to me (I did my research at the time and found similar cases on this forum).

 

check positive post if the batt and alt are goiod. may just have a bad connection there. happened in my redline. couldnt figure it out, until i had to pull the post for something and when i put it back on i never had that priblem again.