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Fuel - shall I be concerned if I don't drive much?

I tend to drive only five to ten-miles per week.

I do occasionally try to drive for 20 - 30-minutes to “boil the water out of the oil” but my concern is about the gasoline.

I’ve read about the issues with funky old fuel, well described on the Stabil web site.

I typically will fill my tank when it gets to 3/4 full (to help minimize condensation … if that even is still an issue with modern cars). But…that means that most of the fuel is many months old. It would seem to me that the fuel would get funky.

My owner’s manual warns against using any gasoline additives. (it is a 2006 BMW X3, 3.0-liter straight 6, naturally aspiring engine).

I only use Exxon/Mobil (87 octane since premium is not required, just recommended and the engine never knocks - and even if that degrades the power and torque, I don’t really care).

It might be my imagination, but I recently did a 200+ mile drive and did not refuel until the tank was about 1/3 full - it might have run “smoother” after the new fuel was added - but since I was looking for a change, it could have just been my mind thinking it did.

ps: I keep my battery plugged into a battery charger/maintainer so I’m not worried about that.

You’re probably fine.

How large is the gas tank? Now estimate how many gallons you might one in a normal month. Report.

I’d say that if you basically use about the equivalent of a tankful of gas within about 6 months then you probably have nothing to worry about.

Other than that a dose of Stabil per the equivalent of about a tank of gasoline won’t hurt anything, though I have gone to using SeaFoam as a fuel stabilizer and a few ounces of that twice a year to stabilize the fuel absolutely won’t hurt anything either.

So a bottle of “Stabil” now and then won’t hurt anything…In your case, every 4th fill-up…

If you keep the tank full or close to it, you should be fine. A bottle of Stabil once in a while wouldn’t hurt either, like Caddyman said.

I agree that (1) you’r eprobably fine and (2) an occasional bottle of gas stilizer wouldn’t hurt.

As to whether you got better mileage on your trip, you probably did. However it can be almost impossible to differentiate between actual improvement and perceived improvement. My feeling is that it doesn;t matter. If you had a good trip, and everything’s running great, than be happy. If you believe you got better mileage, or get better mileage for having gone on the trip, than enjoy the moment. Take more trips.

Life’s short. There are two rules:

  1. don’t sweat the small stuff
  2. it’s ALL small stuff.

Happy motoring.

I’d put in a bottle of Stabil every 6 months, even though it sounds like you’re going through several tanks a year. Just to be sure…

I had old fuel problems with my 79 till I started using Stabil.
BUT
It holds 30 gallons and the truck is driven about 40 miles…a year !

You’ll have to do your math on this one to see if you’re using up the fuel in the tank in a year’s time.
If not, use Stabil.

Hard starting, running rough ? old fuel.
Sniff it, it should smell like gasoline. Old gas doesn’t smell right, you can tell.

If you live in a warmer climate, a little more concern. Cooler, less so. I would add Stabile for ethanol every other fill up during warm weather. If you go through a full tank in less then 6weeks, I woudn’t worry at all.

This is just my opinion, but I’d be less concerned about condensation and more concerned about stale fuel, so I wouldn’t keep the tank that full and I’d add stabilizer.

I’d suggest checking your fuel filter and changing it “frequently” (whatever that means). I had some problems with “bad gas” (which included corrosion in the fuel tank) and the filter sure saved me from lots of engine damage. It also let me know I needed a new tank. I used to have one of the small, clear, add-on filters that you could check visually but I haven’t seen them around for a long time.

One hint: if you check the fuel filter yourself, use impermeable gloves and know what you are doing. Before I did, I spilled about a quart of fuel on our garage floor and my hands smelled like high-test for a long time. good luck!

I am worried more about driving more with $4 + gasoline.