What is the longest you should let a P car sit without having to use a battery tender? I usually drive my 997S on the weekends but it sits home during the week. I hate to let it sit more than a week without driving. I got it all cleaned and gassed up last weekend and didn't feel like getting it all dirty in the pouring rain this weekend. Lousy weather of late in California! Also if the car does sit, is it better to leave the gas tank full, empty or does it matter??
Jim

 

Drive it and re-wash it...I don't drive mine as much since it's for sale and knowing my luck some cell-phone texting person will hit me...

 

Better to top off the tank....it will prevent condensation inside the tank.

 

Yep what he said, and if its going to sit for a long time. Put some fuel stabilizer in it to prevent the fuel from breaking down.

 

What do you guys consider a "long" time?

 

If the car sits for more than 1 week, it should be connected to a battery maintainer. I also assume that if the car is driven, it runs long enough to recharge the battery. A few miles is not enough.

 

Man......I'm a bad Porsche owner; mine hasn't been out of the garage in about 4 months.

 

Every time you drive the car, it needs to be long enough to recharge/replace what was "taken" from the battery during the time it sat...not to mention what it lost just starting the car. There is no way to really know if you're putting back what has been drained in a car that only gets driven occasionally. If there is a net loss over time...one day it won't start. May take a 6 months, may take 2 years...but it WILL happen. If it's not a daily driver, it should be on a tender. Period. Sure there will be those that chime in..."no, never had one, been fine, etc., etc.". It just hasn't happened to you YET.

J

 

For the fuel I'd say anything more than a month. Gasoline does have some shelf life but not to much. Also add the recommended amount of stabilizer. I had a buddy that added way too much and his bike wouldn't start when spring came.

Like adias said A trickle charger or battery maintainer is a good think to also have if your not driving it often.

 

Be careful with an unknown 'trickle charger'. Use either the Porsche unit, or CTek, or Deltran (Battery Tender). These units control the current charging profile and float the peak charge without over-charging.

 

1) Ideally the car ought to be driven daily for distances (or time) long enough to charge .

Realistically -- I have let three weeks go with no issue but try to drive the cars twice a week .

I also change the battery premptively .

2) I leave the tank wherever it happens to be .

 

Mine sat for 3 weeks while I was in Europe, I wasn't about to give the keys to my buddy to take it around the block every couple of days When I got back, the car door lock didn't work, but I manually turned the door key (remember that?) and cranked up the engine and ...... it worked, no problem, the gas was 1/2 tank...

hope that helps.

ak

 

Normal -

The remote-control standby function
switches off after 7 days

2. Press button

 

much simpler approach is to drive it and not to wash it. so you can drive it next time no matter what conditions you got.

 

I killed my BMW 550i battery in 3 yrs with infrequent driving (~6k miles/yr) and mostly short trips. And BMW doesn't go on and on about the battery like Porsche does, so now I keep a CTEK on the 911 all the time. I reckon in 3 years I find out how that goes. It is comforting to come out and find the Green fully charged indicator lit most of the time now.

The CTEK version (same as what Porsche sells, just different logo) is not expensive, and it is easy to use. I think Porsche knows a lot of owners don't drive these cars enough and that is why they (and other sports car makers) market the CTEK chargers with the cars and some even include them with the car.