How long can fuel stay in the tank safely?
 

So.... my boxster has been garaged since May 16, 2011. At that time I ran it (she ran great!) then I put about 3/4 of a tank of Chevron Premium fuel before I put her back in the garage. I have been working out of state where my boxster is garaged and I haven't had a chance to run it since then. (I did not put any fuel stabilizer because I didn't think I was going to be away for this long.) I should be heading back sometime in September, but I need some advice on the fuel issue. Should I try to siphon some fuel out and then add some new fuel before I start it or do you think the fuel is still ok as it is. The temperature in the garage has been about 95 degrees F at the most and no colder than 55 degrees F.

Please give me your thoughts.

Thanks.

Mark

2002 S Artic Silver

You'll be fine. In the future, fill the task all the way when you are going to leave the car for a while to avoid water condensation in the tank. And pop the frunk in case the battery goes dead.

Opinions vary, but in general gas is good for about a year. Maybe more, maybe less, depending on the conditions.

With only a few months of storage, you should be good to go in September. If you want to feel better; start it, drive to a nearby gas station and top it off with fresh fuel. No worries.

With stabilizer added and thoroughly mixed, gas with up to 10% EtOH is good for about 2 years. By itself, about 9 months to a year is about the limit. When you get home, add Stabil to the tank and then take the car for a brief ride to mix it in and you should be fine.

Corrosion from water separation has become a significant enough issue that many OEM’s, Porsche included, that they have begun recommending using additives in all alcohol containing gas, particularly in damp environments, even if the car is a daily driver.

I store my '03 Boxster 6 months of the year, Nov-Apr. I top off the tank and hook up the batttery tender, I'm good to go. I live in WI so it gets plenty cold. The May 1st start up is instant without any problems.
Good luck!