I have been storing my car since August and I had to leave for school early and did not get to use the gas that was in it and I had to leave it with a full tank. Last weekend I went to start it and drive it around for a little bit, and the car felt like it was running really "slugish". Can the gas go bad? If it has is it going to hurt my engine to use it or do I need to have it drained somehow?

 

Here's the likelihood; August, you may as well say it's part-water by now. Yes, that is why it feels sluggish but you must take it easy on it until you run out of the old fuel and flush through some new! You are probably getting some detonation from the bad gas which is causing the knock module to pull some timing (fortunately) to keep it out of knock. Since it's pulling timing you are losing a lot of power but the module's trying to protect your engine in doing so. Best thing to do is either drain it out or drive it out eeeeeeasy! Get a two gallon can of gas and put it in the trunk....drive it until you run out and put the gas in, go to a gas station and put a 1/4 tank in. Drive it until that gets low and put a couple more gallons in. Drive till that gets low and then start driving/filling like normal again. Replace your fuel filter.

 

I went 9 months and all was good

 

Best thing to do is start adding fresh fuel every day or two. Mixing in fresh fuel with the old stuff will rejuvinate it a little bit, and then you don't have to wait for a full tank to be burned off before the performance starts improving.

 

Never had any problems with gas going bad. I'm storing my car each year for 6 months. Just make sure you have full tank, otherwise you can get water in the fuel due to condensation.

I assume the battery cable was off ? So this slugishness was may-be due to resetted PCM ?

 

Est96z28,

The battery cable was pulled off, but what do you mean about the PCM resetting? I have never heard of that. Will it reset again? I don't want my car running like that all of the time!

 

The PCM learns your driving style. If you disconnect the battery it unlearns. It will learn again.

Gas life. Depends on the container. If the container is air tight gas will last a long time.

 

my jeep had been sitting for 8 years when i bought it. It cranked with the 8y/o gas *no point to my story i just thought that it was interesting*

 

Interesting point. I was advised by my tuner to keep just a little bit of gas in at all times so I will have to replace often and keep it fresh. But I see your point and I think I've heard that before. Basically you're saying a semi-empty tank will have condensation on the inner lining above the fuel which turns to water and then mixes with the fuel when you drive.....right? Makes sense. Plus, I would think any impurities in the fuel would be more diluted if you have a full tank. Also, it's much easier on your fuel pump (or pumps) and you have more assurance of full fuel pressure.

BTW, where can you get "Stabil" ....I've never seen it anywhere.

 

Stabil can be bought most auto places... by the gallon even or much smaller amts..
Also, I wouldn't run the tank dry deliberately in these cars unless you like replacing fuel pumps...