Ruskiy

Using one of those lithium ion battery packs... rated at 500CCA with a 997 weak interstate battery reading about 12V (25% state of charge I assume) was NOT successful.

- The headlights started to turn on & off (my poor poor HID bulbs)
- Driver side window rolled down (wtf?)
- Windows wouldn’t auto-roll down so doors wouldn’t close
- Lock/Unlock button stopped working on the dashboard
- Clacking, (relay?) noises happened

Next time I’ll just find a spot with an outlet next to it for trickle charging.

Either way, all this f’n sucked, so I pulled the battery out to charge with my CTEK.

Are there capacitors that’ll discharge and everything reset over next 24-48 hours? I hope I can just toss this battery back in and start fresh once it’s reconditioned & fully charged.

Anything I should know about what to or not to do once healthy battery is back in?

A418t81

Really weird things happen when the battery is very low, as in your case. Everything is almost certainly just fine. Charge/replace your battery and then have at it.

dave292

Did you attached the lithium jumper clips to the positive terminal first then the negative second then, disconnected in reverse order? I was with a friend last week who used one to jump his Porsche and the battery pack worked just fine.
I agree with A418t81, change the battery.

Ruskiy

Yep yep! Positive is in the psgr side and negative on the drivers from what i recall and by checking markings.

The frunk light got brighter and some things in the cabin started working like windows once pack was connected.

All hell broke loose when I turned the key... as if there was just not enough juice in the little battery box. Car battery is running through some reconditioning now then I’ll toss it back in the car and try again.

I’ll leave this jumper pack in my S2000, since it was useless on the Porsche but works great with my Honda.

jeebus31

Same thing happened to me when I was doing a bunch of work on mine and the battery ran all the way down. Car freaked out, windows started going crazy, dash lights all over the place but wouldn't start. Charged it overnight and didn't have any issues starting the next day. You may need to reset your window switches.

Ruskiy

Thanks, is that when I press down and hold for 10seconds once it’s in the bottoms position, then do the same on the way up?

jeebus31

Yes that's correct. You may have PSM or PASM light on but it should clear after a short drive.

Kevin

If the Interstate battery is drained to 8 volts? (fill in the blank less than 11.5 volts) A charge pack will not get enough amperage into the battery to start the engine.

If you have a Interstate lead acid battery it's most likely toast. It will not recover. Go and get it load tested for a bad cell.

Warning, you risk major repair dollars when the voltage drops below 12.3 volts. You can cook your wiring to your starter (glowing RED) when the start voltage drops.

ECU failures, Gauge cluster failure, PSM, PASM, ABS, and alternator diode failures can result $$$

There was a recent thread making battery recommendations >>short version buy a AGM Absorption Glass Mat battery vs lead acid.

o7silverturbo

I hate those small jump packs I melted a positive wire on one of those trying to start a car that was stone dead.

I would suggest charging your battery and then reinstall in the vehicle. These cars don’t really like to be jump started.

Always remember smoke before fire. Negtive then positive when installing the leads

Domer911

all should be fine after a very short trip in the car.

Ruskiy

Thanks guys,
Charged using CTEK, drove for 30min, all is fine. PSM cleared by the time I got to the garage exit.

Obviously we’ll find out about the battery when I try to start it again 2 days from now, if it even starts or cranks slow I’ll replace instead of torturing my electrical system and starter.

Kevin,
I’m looking at other battery thread and the link to AGM battery @ PepBoys. Any re-programming necessary to accept AGM style battery with our platform?

Kevin

No reprogramming. (your CTEK needs to use the cold weather charge setting) The later 997.2TT have AGM from the factory. My 991TTS has AGM Porsche battery new..
The key is the ability to absorb the 150 amp from your alternator on start up. The inrush of CURRENT AND the ability of the AGM to store this current for start up. The Bosch Regulator does a very good job with AGM's.
Look at post 32 on the following link. Look at the volts..
https://rennlist.com/forums/991-turb...battery-3.html

We need to measure the resting voltage of our battery.. We should see 12.65 minimum with lead acid to 12.78 to 12.85 with the AGM.. Tired LEAD ACID batteries allow the voltage to tank below 12 volts many times on start up. Which is very hard on the ECU and Gauge cluster.

I am just trying to offer encouragement for all of use. I'd make a campaign to get rid of ALL lead acid batteries since they have given up on quality vs price point. As consumers, we haven't had a decent lead acid battery in 15 years.

Ruskiy

Thanks for the prompt and detailed response, also, 991Turbo, I’m jealous.

I’ll watch my voltage for sure and then anyways buy that AGM since it’s available now at the store near me. I just checked .

Any down sides to AGM from your experience? It’s hard to find TRUE head-to-head comparisons online and YouTube... I’m a person who loves actual statistics and tests with data yet on the web it’s hard (for me) to find someone spitting stats with data to back it up on the screen through live tests.

Edit: I noticed that the weight specs on PepBoys is higher too for the AGM unit by a few pounds. Weird. Has to be an error.

Antigravity

Just want to clarify a few things...

We , Antigravity Batteries also make the Small Lithium Jump Packs... pretty much the first company that came out with them in 2013... and was Consumer Reports Best Rated Jump Starter for our MICRO-START XP-10 model.... So wanted to clarify that even at 8v or even 4v (severely over-discharge and battery is damage at this point) you could start a vehicle with something like our XP-10... and this is because it depends on the SIZE of the Jump-Packs Battery you are trying to use. The XP-10 is 18,000mah (miili-amp hours) and is still pocket sized and can start Diesels up to 7.3 liters... but something like the Costco models or our tiny models would not fair as well if the battery is severly over-discharged being they are usually only 8000mah... . This is also because the very large Lead/Acid battery is wanting to pull a lot of energy form the smaller jump packs since it is in such a low state of charge. But on a Jump Pack with a larger high quality internal battery it could do it easily. So it about the quality of your jump pack and internal battery size. So look for that depending on what you want to use your mini jump pack for.

Kevin

When you are looking at thousands of dollars worth of electronic DME's it's better to pull the battery and either try to charge it on the bench or Go to Pep Boys and spend $150 for a new AGM Bosch battery.
Call an Uber if you are stranded and if the 997TT is your only wheels. Don't put jumper cables on a dead battery or jump box. Bad things happen.