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Old Gas?

I am going away for 6 weeks and want to know whether I should leave my gas tank full or nearly empty and if I should upgrade to premium fuel if leaving it for the summer in Pennsylvania.

Use the same fuel you always use (my Volvo V70XC liked premium) and add fuel stabilizer to the fuel as directed on the label. I’d leave the tank close to full. Premium fuel is not any more stable than regular fuel for car being stored.

Thank you very much! I will do as you suggest. BTW, I have had Volvo wagons since 1970 and always followed the advice of the dealer and manual to use premium fuel. Mine is now a 2001 V70 and when the fuel prices soared, the dealer said it was fine to use regular gas. I have for a few years and there is no difference in performance. I wonder if it is this model or if I have wasted money on premium for 25 years. If so, I hate calculate the loss! Again many thanks.

Fill the tank with fresh gas, add plenty of stabilizer by direction and drive the car to get it into the system. Top off the tank with a gas and a little more stabilizer. Just adding stabil w/o driving it is only half the job. The more air tight, cool and full the tank, the longer the gas will last. (theoretically indefinitely in a full, air tight container) But warm weather and non air tight container is worse for gas break down. Gas tank is fine with those precautions. Premium does nothing for you if not required by your car.

Six weeks or months? Weeks is nothing. Six months, add the stabilizer and disconnect the battery.

Six weeks??? You don’t need to do anything for six weeks. Although I would like to have at least half a tank full.

I might make one suggestion. If you are not parked in a garage or a safe location, you would be advised to remove the battery. That makes it a lot more difficult to steal. Not many thieves have a spare battery around, and it will also keep your battery from going flat.

Premium gas is not “better” gas, it just means it burns a little slower and works better for high compression engines. Using low octane gas in an engine that requires high octane can damage the engine and/or reduce power and mileage.

fill the tank with the same gas you always use. Six weeks is not long term storage. It’s just parking. Don’t worry.

My lawn tractor always starts right up in the spring after sitting w/ last years gas and battery connected all winter. Amazing. 5 years ;and still on original battery!

I have a 93 Caprice that gets driven once or twice a week. With all the snow last winter it wasn’t driven much and went 3 months between fill ups with no ill effect. Put a full tank of gas in the car to minimize condensation, disconnect the battery and if it makes you better pour a bottle of Stabil in the gas tank.

Ed B.

No big deal…Cars at the dealership sit longer than that with a partially full tank.

3 months of storage in the winter, is significantly different than 3 months in the summer. You can’t generalize about gas degredation when temperature and how tight the container is so important and can’t be compared. But 6 weeks is no problem in some one else car…I recommend it, not because it’s only 6 weeks, but unforeseen circumstances on a sitting car in summer weather could lengthen time and it’s a CYA.

Your motor has a knock sensor and adjust itself to the octane in the fuel. If regular works fine for you then all is OK.

For the OP, I agree to not worry about it, since 6 weeks is nothing to worry about.

However, I used to work in a lawn mower/snowblower repair shop. Many of the mowers/blowers brought in after sitting for the “off season” would not start and their carburetors were plugged solid with a solid varnish. It was the gas that turned to varnish.

I am a big believer in using fuel stabilizer for any lawn mover or snow blower that is stored in the “off season”.

Your motor has a knock sensor and adjust itself to the octane in the fuel. If regular works fine for you then all is OK

But if the owner’s manual calls for premium, then using regular will reduce power and mileage.

I always siphon the gas from my mower and snowblower and “run off” the fuel in the lines for off-season storage.

I also mix carb ir injector cleaner in the lawn-gear gas at a ratio of about 1 to 2 oz of additive for every gallon of gas. It helps keep the fuel system clean during the season’s use. I’ve even had it clean up an old snowblower and get it running right again.