marine2149

Did a Ls1 swap on my 94 trans. My battery now drains really fast. While I drive the colts hover around 9v. If I leave the battery connected overnight it will drain.

​​​​​also while test driving it I noticed my battery drained so much that my dash lights became extremely dim. Parked it and the battery drained completely. So I buy a new battery bc this one was old anyways. Installed the old battery in my truck and fired right up, maybe a bit of hesitation but prob due to the battery being drained by the trans am. So the new battery is in now and it begins to drain. Than all of a sudden after WOT it jumps to normal vols(13.5v-14v). Hovers there for 5mins and then proceeds to drop low.

can't figure this out. I rewired PCM hoping it's nothing there bc that's Alot of wires. I'm thinking my battery cables are not grounded well or I forgot to install some grounds somewhere during the swap. I had two copper grounding cables left over after my build. Dunno if they were Lt1 specific or I missed something. I installed the ground that gets attached to the heads and the ones attached to the support in front of the radiator. Other than that I'm lost.

. Any help I would appreciate. Thanks.

Pop N Wood

iTrader: (1)

Its not grounds. You have something shorting out and/or constantly turned on.

Disconnect the positive battery cable and and hook an ammeter in line between it and the battery post. See what the current reading is, should be zero or fractions of an amp. If it is higher, start pulling fuses until the current draw drops. That is the circuit you need to concentrate on, something is permanently wired on or shorted out.

If you still have a current draw with all the fuses pulled than start tracing wires and see if something is chaffed or grounding to a piece of sheet metal.

No fun.

marine2149

Thanks I will try this today.

marine2149

Thanks. Anyone else have suggestions as to what it could be.

marine2149

Update: drove the car for about an hour. Volts dropped to 8-9v and and eventually it drained the car off.

​​​​​​ So I come off the freeway after an hour of driving and turn right. My volts jump back up to 13v. immediately after peak volts, it began dropping back to 8-9v within 100yards.

. Could this be a loose battery cable? I feel like I might have a bad ground. Anyways thanks for the info guys.

marine2149

Update: drove the car for about an hour. Volts dropped to 8-9v and and eventually it drained the car off.

​​​​​​ So I come off the freeway after an hour of driving and turn right. My volts jump back up to 13v. immediately after peak volts, it began dropping back to 8-9v within 100yards.

. Could this be a loose battery cable? I feel like I might have a bad ground. Anyways thanks for the info guys.

1964SS

iTrader: (1)

A loose battery cable or bad connection can cause a volt meter to drop, but it will not drain a battery. Did you do as suggested to locate any current draw and pull fuses to find the issue?

You will need to trouble shoot this issue.

Project GatTagO

iTrader: (7)

How about the obvious? Maybe your alternator is junk? If you put a fresh battery in it and it drained while driving, then your alternator is not working.

Andrew

Pop N Wood

iTrader: (1)

Unfortunately the battery also drained with the motor off. Could be a bad alternator, but my guess something is wired wrong causing both the current drain AND the alternator to not charge.

A loose connection could be the issue. A wire shorting to ground could be it as well.

Unfortunately you are going to have to start tracing wires.

pdxmotorhead

Bad diodes in the alternator will drain the battery and not charge correctly..

64post

iTrader: (5)

This ^^^ with a multimeter set on miliamps and in series with pos cable and pos bat pole, start pulling fuses 1 at time until the mA reading goes below 40-50 mA. Disconnect your bat. Wire to the alt and see if the reading drops to acceptable level, if so, bad alt.
The most common parasitic battery drain causes: aftermarket stereos and amps, alarms, relays stuck closed, glove box light, trunk light, alternator diodes and ?

marine2149

Update: bought a new battery bc I broke my old one. I mixed up some cables and the pos terminal melted. Lol I'm out 100$. Lesson learned. So my car does not drain anymore but the volts take a hit occasionally. Drops down to 7-8v. Sometimes when I run over a pot hole or make left turns my volts will jump back up to 13v as if my alternator connection was loose. Tried tighting the connector on the back but only goes so far. A bit afraid of breaking the plastic cover. I was informed there should be a washer between the connector. I'll look up the diagram when I'm off.

note. I'll shut my car off and 1 min later I'll hear a low metal clunk. Sounds like a relay engaging.

thanks for all the info guys I feel as Ian close to figuring this out.

andrew69_04

iTrader: (148)

read post 2. Thats the best way to find your issue before you end up burning your car to the ground or causing other issues having something hooked up wrong. If your getting a bad drain, you have wiring done incorrectly. The method listed in post 2 will point you directly to your problem. I've used that method on several vehicles and it's never failed me yet.

LilJayV10

iTrader: (39)

take it to a shop

marine2149

So for anyone who might be having this problem hear it goes. I FIXED IT!! It was the terminal on the back of the alternator that was loose from its base, allowing the tighented battery cable to move freely along with the terminal. Explains why my alternator would charge after making sharp turns or running over pit holes. Volts would drain until the car died.

. But I tighented it and now my volts read 12.5-13+ depending on conditions. Have not tested the fuss for possible leaks since before I tightened the alt. Regardless they did not register any drain. I will try again soon and keep you guys updated. Thanks for all the replies. Must alpricated.

marine2149

So for anyone who might be having this problem hear it goes. I FIXED IT!! It was the terminal on the back of the alternator that was loose from its base, allowing the tighented battery cable to move freely along with the terminal. Explains why my alternator would charge after making sharp turns or running over pit holes. Volts would drain until the car died.

. But I tighented it and now my volts read 12.5-13+ depending on conditions. Have not tested the fuss for possible leaks since before I tightened the alt. Regardless they did not register any drain. I will try again soon and keep you guys updated. Thanks for all the replies. Must alpricated.

Pop N Wood

iTrader: (1)

Your running volts should be closer to 14 V.

Fully charge the battery and see what it is. If still 12.5-13 than you still have a problem.

Also a loose alternator power cable doesn't explain the battery draining with the motor off. Maybe you fixed something with all your other changes or maybe the battery was just so weak from the alternator not working.

Either way I wouldn't plan any long trips until you get some solid run time and can make sure you don't still have an issue.

marine2149

good advice, ill be looking into other problems soon. correction its more around 14v im just going of the top of my head. it will drop depending the load i have in the car. upon start up it reads around 14v. ill keep an eye on it. thanks for the info.