I have a 1998 Acura Integra Type-R. My battery kept draining. I bought a new battery, it drained, so I had my alternator re-built. After installing re-built alternator check voltage from alternator with car on and it was only putting out 12.1 volts. Battery kept dying. I just bought a new alternator thinking the re-build was no good and same thing happens alternator wont charge. I've checked all my fuses everything is good, I want to check all the ground wires but don;t know where they are located....Ive also read that the ecu controls the alternator so I pulled the ecu to see if anything was fried and it was fine. Any ideas???

Who replaced the part's ? have you had the vehicle to a qualified repair shop ? What made you think the alternator was the cause for the battery drain ?
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Hooking up a professional scanner an viewing data parameters for sensors is the proper way to diagnose . Did you clean throttle plate , iac passages etc.. What does scan data for TPS look like , are the O2 sensors switching normally , IAC counts etc....

You may have a bad diode in the alternator. Or bad connection somewhere. Is the new battery draining?

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There is an electrical short draining the battery. . You can check each fuse one at a time to find the circuit & trace the wire to find the short. Make sure all electrical things are working, if u find something not working you can strt looking through that circuit for the short

the battery wont stay charged? if youre putting in a fully charged battery and your car runs, but then the battery slowly dies, the problem will be your alternator. the alternator is what maintains a car batteries charge. try replacing the alternator. hope this helps.

if you suspect your alternator disconnect power going to it and see if your problem is over

usually you have something electrical draining your battery so please check any new items installed or you may have a bad alternator as this will definitely drain your battery. You can have this tested at your local parts store.

Check the main power fuse that goes to the alternator output. if the alternator went out it could have burnt this fuse also.

Hi. lets isolate this drain. thsi will make it much easier to repair. use the procedure below.

Here is the procedure I use to isolate a battery drain. Remove negative battery cable from the battery. Using a 12-volt test light, hook one end to the negative battery post the other end to the negative battery cable you just disconnected. The test light will glow or "light" if there is a drain. If the "light or glow" is faint, that is probably normal draw for the clock or computer. If the "light or glow" is bright, then there is a large drain. That should be corrected. Now start removing and replacing the fuses one by one until the light goes out; that one will be the circuit with the drain. Remember to hold in the button in the door jam for the interior lights.

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