battery draining every 2 weeks after sitting

[Kyle.malone]

Where to start. The probelm didn't start until I added the EFI. The only thing wired directly to the battery is the computer main power. The RJM harness said to run directly to power with a keyed switch as well. The Radio I added is on a cutoff. Where should I start looking?

 

[blazinchuck]

run a test light between the neg cable and neg post on batt...if its a good draw...light with come on...then start pulling fuses or unplugging stuff. that should help narrow down where the draw is coming from

 

[patterdale]

Two weeks is probably not unreasonable if the computer is running a drain. I have some experience with VW beatles and alot of them are the same. I we let my wife's sit for two weeks it will not start. A lot of them also need to have some form of power source during a battery change or they lose the radio code and the main computer craps the bed. Then you have to take it to a dealer to get it reset. Everything that has a memory causes a draw and if you don't drive it it won't maintain a charge. It is similar with just running short trips. The alternator wil not always be able to put back what was taken out during starting so eventually the battery is drained down.

 

[1970mule]

sounds normal to me as mine does that also. just get one of those $5 trickle chargers from harbor freight and hook it up when not in use for more than a week. i have a quick disconnect but with an ecu you will loose what the ecu learns everytime you do that.

 

[casadejohnson]

I can let my 74 sit for a couple months and it fires right up. My 66 can go weeks as well, the 68 on the other hand has to be started every couple weeks or it will have a dead battery. I have not even tried to figure it out but the test light technique is going to be my plan of attack if I can find the time to work on it.

 

[broncnaz]

Computer and or stereo shouldnt drain the battery in 2 weeks 2 months maybe. you may have a bad battery or a bad diode in the alternator.

 

[robinsoncc]

Put a disconnect switch at the battery or just take the neg lead off if you are going to let it sit longer than a couple of days.

 

[Viperwolf1]

That's above normal drain. Start by measuring the drain current. Should only be a couple milliamps. If it is, your battery is toast. If it's more, pull fuses and connectors until it goes away.

 

[VB1975Bronco]

Viperwolf1...I am pretty new at this...can you tell me how to "measure the drain current?"

 

[Viperwolf1]

Use an ammeter or multimeter. Place it in-line between a battery terminal and the cable. Positive lead on the most positive (positive battery terminal or neg cable if you disconnected the negative terminal). Negative lead on the most negative. Make sure everything is off first or you can fry your meter. Most can only handle 10 amps momentarily. Read your meter instructions.

 

[green77bronco]

My Opitma red top drains in about two weeks, but I've used
Other Batteries that were fine after a month of sitting.