battery drain HELP PLEASE!!
Thread Starter
Intermediate
Joined: Sep 2009
Posts: 27
Likes: 0
From: Carrollton IL
battery drain HELP PLEASE!!
Got my car back together after a tvs upgrade, ls3 heads and custom blower cam and ever since I have been getting a battery drain while driving. It will start out fine for the first 20 to 30 miles showing between 11.8 to 12 volts but once it gets down to 11.5 it starts dropping like a rock all the way til I loose everything. I thought it was a bad red top so I had it replaced under warranty, still no change so I put a new gm alternator on and same thing. I chased the positive around the back of the motor to the starter and nothing was pinched, connections were tight on starter. I then replaced the horn fuse and micro relay and put a new ac delco battery in, this is driving me nuts. I feel like im chasing a ghost. Car is always left on a battery tender
Pro
Joined: Jul 2012
Posts: 625
Likes: 57
From: San Jose CA
Hook up an ammeter between batt and cable. Shouldn't have more than say 100 milliamp draw with everything off. If it's much more, start pulling fuses until you find the circuit that's drawing it down.
But realistically, if your alternator is working and you have a good batt, something is draining serious juice. You should be close to 14V. You could put an inductive ammeter on the alternator and see if it's really pushing juice.
Check your ground wires, they're just as important.
But realistically, if your alternator is working and you have a good batt, something is draining serious juice. You should be close to 14V. You could put an inductive ammeter on the alternator and see if it's really pushing juice.
Check your ground wires, they're just as important.
