Stale gas a problem??

I believe that is less of a problem with the Prius than with most other gas-using devices due to the fuel bladder and vapor containment systems. It is also a lot less of a problem in vehicles that have fuel injection and ignition control systems than in carbureted engines (ie. chainsaw, string-trimmer, etc). If you are in the habit of leaving the car for months without driving it, Sta-bil may not be a bad idea, but I doubt that bad gas will be your biggest concern if that is the case. If you are driving the Prius at least weekly, I wouldn't worry about it too much.

 

Hi K,

I am with your husband on this: no worries regarding the gasoline. You are going through a tank in about a month which is fine. I assume that you are buying 87 octane regular from a top-tier brand (such as Chevron, Shell, Union 76.)
Top Tier Gasoline

Regarding engine oil changes, if you were not concerned about warranty issues, I would say that annual oil changes are sufficient since you are only driving 5K miles per year. With the low usage, there's no wonder that your car is a magnet for mice.

If your normal driving is lots of short trips (instead of fewer long trips) then it is likely that the 12V auxiliary battery will suffer an early failure.

 

most people I know who have performance cars in the garage run the tank low before storing it. And then whenever they head out they stop at the gas station first thing to put fresh fuel in it.

 

I wouldn't worry about that amount of miles in the Prius. It's true that as the fuel evaporates it will leave yellow crusty junk behind that likes to clog things such as carburetor jets. 1 of my 3 quads is sitting in my garage this very moment with a clogged pilot jet due to this very thing. Anyway, I haven't heard of this problem in a fuel injected vehicle where fuel is sprayed at a very high pressure. In addition, you're not going to have this problem even if your Prius was carburetor as you're driving enough miles to keep fresh (enough) fuel in there. If you were driving a diesel I'd be a bit more concerned as diesel tends to "go bad" faster since it attracts water.

Another thing as mentioned by someone else is the bladder limits the amount of air in the tank as well as the ability for the fuel to evaporate (leaving the junk behind) since there's no where for it to go.

Mike

 

I hope you don't mind my asking but, why do you have a prius that you don't drive much?

I never really pictured the prius as a "weekender" kind of car.

 

I was thinking the same. For the hybrid premium, maybe financially it would have been better to get a Corolla or similar. Everyone has their reasons and I tend to be perhaps more pragmatic than most.

FWIW, I drive about 30,000 miles or so per year...

Rick
#4 2006

 

I had a 1993 Mazda RX-7 for ten years and stored it in the garage every winter for 6 months. I filled the tank and put the car on jackstands (and changed the oil). Each spring I never had a problem. Gas is just fine for almost a year, unless you let it evaporate, such as in a small engine (like the chainsaws you mentioned). Stabil, on the other hand, can mess up the chemical formula that the Prius is expecting. Most of the time people have trouble with small engines is due to the gasoline evaporating and leaving behind "junk" that blocks the tiny passages in the carburetors. I've only seen a few cases of "stale fuel", and it was left for over a year.

An easy way to tell if it was evaporation or "stale fuel" is if they just drained the fuel and put in new did it start? If not it was evaporation, which requires disassembly of the carb. and vigorous cleaning with toxic chemicals.

 

6 weeks after non-use, I had a motorcycle tank of gas go bad. They called it, "turning to varnish" . . . and that's exactly what it smelled like. After driving it around w/ a ton of cleaner in a fresh tank of fuel, it cleaned out. It took about 4 hours of the motor running. It sounded like it was running on only 3 of 4 cylinders untill it cleared.

 

I suggest buying your filters on line from one of the Toyota dealers. I split a $100 order with a coworker and saved about half.

 

Yes, the online price is $15 for the cabin air filter and $13 for the engine air filter. Here is a link to one of the Toyota dealers that sells at 25% off MSRP: http://www.toyotaworld.com/

Minimum UPS ground freight is ~$9 from Houston to Orange County. Hence I usually purchase several items at a time, to get the maximum benefit from the freight charge.

 

Yep. I'd be leery of putting any kind of additive into the bladder.

 

With any modern fuel injected vehicle, "stale" gas is much less of a concern than with a carburetor vehicle. With a carb, the gas can go "stale" after a week

A lot of carbs, especially the older non-emission and performance variety with open element air cleaners, are atmospheric vented. Park such a vehicle in a tightly sealed insulated garage, you'll always smell gasoline fumes. No leaks, just gas evaporating from the carb

You can do a simple experiment to see what happens. Note, safety first, don't do this in the house or a garage with a hot water heater or dryer.

Take a clear shot glass or tumbler, fill it around half full of fresh gasoline, and use a Sharpie to mark the level. Put a piece of paper on top to simulate the air cleaner on a carb.

Now, watch what happens to the gasoline. After a week the level will be around 2/3 or less of what it was fresh, and the fuel will have turned a yellowish color. There will also be gunk at the bottom of the shot glass. After 2-3 more weeks, the fuel will have mostly disappeared, leaving behind a sludgy stuff

That is what happens in a carb unless the vehicle is driven at least every 2-3 days. Worse with Holley carbs, the ones with paper gaskets the gaskets shrink and cover up the idle circuits and enrichment circuits

Now repeat the experiment in a tightly sealed pickle jar, there will be a far different outcome

I'm leery of fuel additives when O2 sensors and catalytic converters are involved. Even if the additive works, it could bugger the O2 sensor or catalyst

In the commercial field, I've had good luck with PRI additives. They also make additives to treat bunker fuel used in ocean ships. Most of their additives are sold by the barrel.

I use their gas additive to treat my stored fuel for my small motors, and the entire tank in my old Ford pickup

PRI Advanced Fuel Treatments

I never store small motors with fuel in the tank or carb. I drain the tanks and run the motor until it quits. I have a couple of small Honda motors, very easy to store as the carb bowl has a drain bolt

Again, in your case I don't think you have too much to worry about