5 Clever tips on how to rejuvenate old gasoline by yourself

Got some old gasoline gathering dust in your storage room? If so, this article’s made for your eyes only. In it, we’ll show you how to rejuvenate old gasoline by yourself with 5 clever tips. Not only that, but we’ll also introduce you to some other old-gasoline-related info. As always, here at GasAnswer, we like to be pretty thorough.

So, what is old gasoline? What is the usual shelf life of gasoline? Also, how can a person test for old (bad) gasoline? We’ll answer those, too. All in all: stick around for some valuable information!

First, you’ll need to know whether you’re able to rejuvenate your old gasoline. If it’s murky or muddy, or you see separate liquid layers, dispose of it in the safest manner. If it’s still clear and doesn’t smell foul, mix it with new gasoline in a 1:1 ratio. You can combine them inside the tank directly.

Only skimming through the snippet isn’t something we’d recommend. Therefore, you should read the whole thing!

Table of Contents

What is the shelf life of gasoline?

Here we’ll consider just how old old gasoline is. In other words, let’s see what the ordinary shelf life of gasoline is. Anyway, regular (unleaded) gasoline will last you about three to six months in storage. Ethanol-blended gasoline will last you about two to three months in total. Lastly, fuel-stabilized gas will have a shelf life of about one to three years.

Keep in mind that these numbers stand only if gas is kept in proper storage conditions. Also, you’ll want to know that diesel will last you a year before it starts to degrade. Lastly, organic-based Ethanol will last you from one to three months. After that period, it will lose its combustibility. All thanks to the processes of oxidation and evaporation.

For more tips on how long gasoline stays inside a red gas can, follow that link. Okay, so let’s what else can we tackle in this introductory section.

How to test for old gasoline?

Once gas gets old, its chemical properties will end up modified. That will cause the engine to start having issues with fuel processing. Okay, so there are a few key indicators that your gasoline’s gone bad. Here we’ll introduce you to them:

  • Your “check engine” light is on. It’s probably the most obvious sign. Anyway, if the mentioned light is on, it might signal that your gas is burning improperly. Your best bet is to take your car to a mechanic for further investigation.
  • Your car’s behavior shows some operational issues. What do we mean by that? Well, your vehicle could fail to start, for instance. Other issues can include a rough-sounding idle, or loss of power while you’re driving. The latter’s especially noticeable while you’re accelerating.
  • Your gasoline has gone dark or muddy in appearance. There’s no need to explain this one. You’ll easily notice this.
  • Your gasoline has gained a sour or suspiciously smelling odor. You’ll know something’s not quite right.

All in all: once you notice any of these symptoms, it’s best you remove the (bad) fuel from your tank. It’s not just about preventing your vehicle from running poorly. Nope. It’s also because bad gas might do some good old damage to your engine’s internal components. Also, it will leave behind a gummy residue that can easily form blockages in the gas line.

Not to mention the fact that Ethanol-blended gas can draw in water vapor. The latter can cause your tank to corrode. Speaking of which, here’s how you’ll clean a fuel tank of rust.

Okay, now that we’ve cleared that one up, it’s time we tackle the main question. In other words, let’s see how you can rejuvenate old gasoline!

A bunch of old gasoline cans in a row.

5 Clever tips on how to rejuvenate old gasoline by yourself

Without further ado, let’s show you the promised tips on how to rejuvenate old gasoline!

Tip #1: Know your limits

Okay, this title might be a bit misleading. We’re talking about knowing whether your old gasoline can be rejuvenated. In other words, you’ll need to know whether your efforts will prove fruitful. Whether your gasoline is simply old, or bad “beyond repair”.

It’s important you’re certain that your gasoline can be rejuvenated. There’s a difference between old and old, bad gasoline. Anyway, here’s the first tip. If you’ve kept Ethanol-blended gas in storage for more than three months, don’t even bother. Simply dispose of it in a safe manner.

Also, if you notice that gasoline started to appear in two or more liquid layers, say goodbye to it.

How to test for bad gasoline?

You’ll need two clear vessels to compare the samples of good gasoline and the one you suppose might be bad. Anyway, pour a little of each into the separate cups. If you notice that your old gasoline is still clear, just slightly darker than new, that’s good. You’ll still be able to rejuvenate it. Steer clear of trying to rejuvenate gasoline that has gone dark or reddish.

Also, if your gas looks a bit cloudy or milky, or there’s something flowing in it, it’s no good. Don’t even try rejuvenating it. A slimy, sludgy, and/or waxy look of gasoline points out that it’s bad beyond saving.

If you’re looking for more info about the process, you’ll find it right here.

Tip #2: Be careful

You’ll want to be super careful in deciding whether you want to put “saved” gasoline in your tank. To phrase it differently, don’t try putting gasoline that can’t be saved inside your tank. Here we’ll show you just what can go wrong if you do it.

As we’ve implied, old gasoline isn’t good for your engine. The least you can get with it is engine knocking. The worst you can get with it is the aforementioned gumming up of the fuel injectors. You might unintentionally cause some long-term harm to your engine.

This was a short warning. Let’s continue!

Tip #3: Bringing back your old gasoline to life

Anyway, here’s a step-by-step guide on how to bring your old gas back to life.

  • If your gasoline isn’t very old, add it to new gasoline in a 1:1 ratio. If, on the other hand, your gasoline IS really old, the ratio should be 3:1 in favor of new gasoline. 
  • You can do this directly in your vehicle’s tank. If your tank’s full of old gas, drain it until it’s half-full. Just so you get it ready for the mixture ratio. Of course, you can do this inside a gas container, too. 
  • Next, shake your container or rock your vehicle slightly in order to make sure old & new gas mix well. 
  • Sip your gas, if you’ve mixed it inside a container. Try to start your engine. It’ll probably take you a few tries. 

Okay, let’s see what are the last two tips!

Tip #4: Detergent additives?

Are you forced to use gasoline that’s on the verge of going really bad? If so, it’s best you do it in the safest manner possible. How to recognize this “barely good” gasoline? Well, it has gone a bit dark or reddish but it’s still clear. In other words, it’s not murky or cloudy.

Keep in mind that this “type” of gas can damage or clog up your crucial engine parts. Needless to say, this can cause major issues for your vehicle. However, there’s something you can do to prevent the worst scenario from happening. That’s right, you can simply add some detergent additive to the aforementioned mixture.

You’ll want to opt for a detergent additive that possesses PEA or PIB detergents. Read the package instructions. That way, you’ll know how much you need to add. All in all: it will help you deal with deposits found on affected engine parts before they harden.

Tip #5: Prevent these issues with a fuel stabilizer

As you could’ve read earlier in the text, a fuel stabilizer can prolong the shelf life of your gasoline. There’s no doubt about it!

What kind of fuel stabilizer should you use? Well, our suggestion is that you choose Sta-Bil as it gets the job done. Most experts would agree with us on this one. There are different versions, as some are fit for Ethanol-blended gasoline. Choose the one that matches the gasoline you’re using.

So, how to use Sta-Bil? Well, it’s fairly simple. You’ll just need to mix it with your gas as soon as possible after purchase. With Sta-Bil, you can expect about three months to a full year of extra shelf life. If that’s not cool, then we don’t know what is!

One last thing. Don’t expect Sta-Bil to somehow rejuvenate your old gasoline as that can’t happen. Sta-Bil doesn’t bring bad gasoline back to life. Sta-Bil only functions with good, fresh gasoline.

Final words on the subject of rejuvenating old gasoline

Okay, folks, so that’s all that we’ve prepared on the subject of rejuvenating old gasoline. Hopefully, you’ve enjoyed reading it as much as we did writing it. We’re not ironic. Anyway, now you know how to give your old gas a second chance.

For more tips & info concerning various gasoline-related topics, visit our blog page.