I have a brand new battery and a good(tested) alternator. But over a few hour period my batttery eventually goes dead. It acts the same with or without the headlights on. My conclusion is that something is draining my battery faster than the alternator can charge it. The volts wont go over 11.40v and it slowly drains from there. Fully charged (11.40v) or not. Any suggestions?
(yeah i know full charge is @14.4v)

 

A fully charged battery is 12.6. That voltage you mention I'm asumming is with the car running. Ether you alternator is bad or... the single wire off the alternator is bad.

 

not to judge your intelligence but im pretty sure that the gauge on all my previous 3rd gen f-bods has always been over the 13.0v mark. The car that i have now has been over the 13.0v mark until now. So maybe we have a different definition of fully charged. Im talkin about the regulated voltage that the alternator maintains on the car while the car is running. Please explain b/c im not a genious on "DC" current.

 

O.K. I gues I needed to be a little more spacific. A fully charged battery will be 12.6 volts By its self with out the alternator.... A battery with a working altenator will produce 13.2 to 14.??? vOLTS. Get you self a multimeter and check it that way. I don't rely on my gauges only when I notice a problem. I currently have a 180 amp alternatorein my car that by my gauge says its only got 12.3 volts. Hook a meter up to the battery I get 14.3. Hook it up to the alt and get 14.3. So the bottom line is either your gauge in the car is messed up, your alternator is bad, or you have a wiring problem.

 

Yeah, GM's factory gauges suck. You need to use a multimeter to test accurately. If you have verified that you are only getting 11.6v with the car running, you're alternator is not charging the car. Check to make sure the alternator has a solid connection to the engine (ground), and make sure that you have a good solid connection from the back of the head to the firewall. Or, like camaro-60181 said, you could have a bad connection on the charging wire.

If you are only reading 11.6v on a new battery with the car off, you either have a defective battery, or like you suspect you have a voltage draw. In order to completely drain the battery in a few hours, that has to be a pretty big draw. Try this: With the doors closed, all accessories off, and the hood light disconnected, disconnect the battery and then reconnect it. When you reconnect it, you should have NO sparking at the terminals. If it sparks, that means that something in the car is drawing voltage.

Let us know what happens,
Matt

EDIT: if you have a voltage draw, check any aftermarket wiring and accessories first. Chances are good that the problem lies with a faulty install or cheap components.

 

ok this may sound stupid but i had almost the exact same problems with my ROC. check your fuse box for any loose fuses, im not sure which one it was as my fuse block is so worn out but there is one there that if loose or not there, will cause the batt to drain when the car is on.

check the connectors too if theyre in good condition

 

sorry guys i havent replied, just been real busy trying to get to and from work. Thanks for all your help though. Come to find out the previous owner had a "remote?" wire running to the fuse block from the Alt. and i kicked it out. Where was you at before i bought a new batt. Camaro 67 LOL. But i found it yesterday and solved all my problems. Thanks Alot Guys.

p.s. And no that didnt sound stupid Camaro.