Battery going dead over night

[The Harm]

I recently had a fuel injection propblem. #2 injector was being pulsed to too often. Later found out that the computer was the problem. So I replaced the computer with a remained unit from autocomp in Houston Tx, and the car runs great however the battery has been going dead every night since I put the new computer in. I did notice a buzzing noise for about 3 seconds after I turned the car off and removed the key from the ignition. I turned the car on and then off again to see if the sounds happend again and maybe hear where it was coming from. It sounds like the sound is coming from the area of the ECM. Could this be the problem?? Has this happened to anyone else??? Ideas??

 

[luv2rallye]

Here's how to find your battery drain: http://www.dsmtuners.com/forums/showthread.php?p=1496998#post1496998

 

[dyno_detour]

Is your alternator working properly?

 

[gottalovenewage]

go to autozone and have them check your alternator/battery for free. while the redshirt is out there doing that, have him/her check the cables and cable ends for corrosion. man i say that way too often, .

 

[91Bomb]

If you're sure your alt is good you could pull the battery out overnight + see how it is in the morning checking it with a voltmeter. If both are good I'd look at the mpi relay + the ecu. That noise you're hearing is probably the mpi relay opening and closing and could either be malfunctioning on its own or because of the ecu. There's a simple test that can be done to check that relay.