Hey guys. I have a 96 Honda Civic CX. It's been sitting in my garage undriven for the past six months. (It was never driven heavily but this is the longest it's ever sat.) Tires still appear to be inflated well. Battery is on a battery tender, and it was filled up with a full tank of gas right before parking it. It's been in a garage in northern california, but we have had a couple heat waves recently reaching temps over 100F in case that's relevant. Should also mention the battery is not in the car itself; it's been out of the car for 2 months.

My question: I have a couple bottles of STA-BIL. However, I have not had a chance to add any in the tank. I might be starting the car up tomorrow to try and get it smogged. I am not sure how long I will be driving it after that; I might go through that tank of gas or I might just re-park it after the test. A few questions (1) Should I put one of the bottles of STA-BIL in right away, regardless if I plan to drive it or not? (I have two bottles). (2) Is that 6 month old gas going to damage the car if I drive on it? (3) Would it be OK to add STA-BIL to the existing gas, and then re-park for another 6 months or so, or must I exhaust the tank and re-fill with new gas before letting it sit again? (I don't really have the ability to drain the tank unfortunately.) Finally, (4) Any general advice you might give? (Either about letting it sit long term again, or smogging it tomorrow after sitting for so long?) Tomorrow I will be changing the air filter, and then driving the car for a good 20 minutes before I take it to the smog station.

Any advice appreciated guys. Sorry for all the questions; don't feel obligated to answer them all...

 

6 month old gas isn’t ideal but honestly probably wouldn’t noticeably hurt anything. If you are worried about it, these cars actually have a fuel tank drain bolt so to drain the tank all you need to do is lift the rear end up and pull the bolt out. And if you are going to let it sit a while, I’d make a point to not have a full tank of gas in the car, that way it won’t be a problem in the future.

 

Hey, yeah I wish I could just drain it but unfortunately I don't have any jacks nor do I have a bucket or even anywhere to do it. About keeping a full tank before parking it, I read this is better than keeping it on an empty tank because it helps prevent condensation in the gas tank. Not sure the details of this though? (I imagine it must be different if you're parking it for 6 months, or a year, or 5 years etc. ??)

In my case parking it on a full tank was coincidental though. I didn't expect it would end up not being driven for so long.