So last year towards the end of fall it sounded like the car (‘04 350Z) was cranking slower than usual. Stuck it in the garage for the winter and after about 1-1/2 months needed to charge the battery (overnight) to get it to crank over. A month later did the same thing. About 2 weeks ago charged it up overnight and got it back on the road, still a slower crank but starts...until it didn’t (Walmart parking lot after work). Don’t scold me too much, I know **** batteries, but went back in and got a new one which fired it right up and with WAY more cranking speed. Searched here about parasitic drains and threw a meter on it. Getting 0.113 amp draw. Pulled every fuse (all 3 places) and also disconnected my amp line and DRL relay (diy for aftermarket headlights)...only change I got was down to 0.108 when I pull either of the radio fuses. Just to be thorough, when I first connect the meter it shows about 0.440, then drops to 0.185, and then settles to 0.111/113 and stays there. Have no idea why it would surge like that at first. Any help or insight is greatly appreciated.

 

One important detail left out of your post is how old your battery was before it was replaced. Car batteries have a limited lifespan and if it was 3-5 years old, it may have simply lost charge and had less CCA after sitting for the winter.

 

The original battery was also cheap and if memory serves was 2 years old, but it had also been discharged during winter storage both times to the point of being nearly dead.

 

Since this battery was nearly depleted 2X, it may have been damaged past the point it can be salvaged. The easiest and likely, cheapest, fix is to simply replace it and see if the new battery is following the same path. Unless you have a significant mod that is pulling power, there shouldn't be a huge parasitic draw.

 

I guess the question I need answered is what is considered a parasitic draw? Are we talking a couple milliamps or can it be in the tenth of an amp range (100 milliamps). If it’s the latter then I’m fine at 0.115. If it’s the former then something is wrong and I need to get it figured out. I typically only drive for no more than 15 minutes at a time so there is little opportunity for the battery to get recharged by the alternator. I guess if I can’t get it figured out then a better tender will be the answer.