Starting issue/battery drain
 

So i bought a 986 on copart dith 45k miles.

Put a new battery in. It started and ran great.

About a month later, i washed it. It got cold overnight and froze.

Next day, i noticed it was dripping. Popped frunk to take a look. The drain got clogged. Filled with water and ice in bsttery bay. I cleared clog.

Ever since, the battery drains and it wont start unless i jump it. Even if i drive it for an hour or more. I turn it off, it wont start unless i jump it agsin. When i jump it, the jumper cables get super warm.

What happened?

Newbie

Have you had the battery tested? Just because it’s new doesn’t mean it’s good.

+1 Occam's razor

I buy & sell Porsches as a hobby. 5 yrs ago I bought an 09 base Box. Got it home from Tucson and it'd keep a charge for about 4 days. Recharge and it would be fine for 3 days. Battery was only a yr old, so I was certain that wasn't the issue. I was all set to start a parasitic drain search and contacted the sage of 986forum (JLP in PA) for advise. He said to start with the simple things first (Occam's razor) and be sure they aren't the cause of your problems. Took the battery to a local parts store and sure enough, it was bad. Bought a new battery and no more issues. Checking a battery is an easy 1st step and can save you a lot of time if it's bad. Been applying this lesson to any search for a problem's solution since then.

If your battery checks out fine, move to your radio. Is it an aftermkt version? Unplug it for a few days and see what happens.

Next up, are there any other aftermkt items in the car? Unplug them and see what happens.

Then you're into the full multimeter / pulling fuses mode. Time consuming and not a lot of fun.

Good luck.

Have the battery load tested to make sure it is still good.
Make sure the battery tray the battery is setting on is dry.
Make sure the top of the battery is dry.
Make sure both cable connections at the battery are clean (bright) dry and tight.
Make sure the connection of the negative battery cable to the car frame is clean (bright) dry and tight.

The fact that your jumper cables get hot when jumping the car shows that you have resistance to the current flow some where in the starting circuit. Resistance to current flow is usually caused be poor connections or bad cables.

Hmmm. The only thing aftermarket is the radio. When i first got the car... radio didnt work. Had a blown fuse. I replaced the fuse and it was around this time i started having issues with the battery/starting. Interesting

The hot wire running to the radio might not be totally losing connection after you remove the key. Or the "memory" function of the radio which stores the radio stations and whatnot could be draining it as well .It sounds like you should definitely investigate there.