[nsoltz]

A friend raised a question-- should the gasoline in the PHEV be at least partially consumed periodically? My wife drives the Niro primarily around town and in the few week's we've had it, minimal gasoline useage. In fact, the fuel gauge is just one notch below full (and there are 16 notches). I did some research and found that Chrysler Pacific and the Chevy PHEV have maintenance modes which circulate the gasoline in the tank and in fact even use some.


Any ideas about this concern in the Niro PHEV?

 

[FlNiro]

I wonder what Kia says about this? I wonder if it makes sense to put in the additive that is used for motorcycles when they sit over the winter?

 

[dots]

I own a Pacifica Hybrid, and it indeed has an "oil and refresh mode", which basically forces the ICE to turn on if it determines it has been too long since you last filled up. I've gone almost 3 months without a fillup in the PacHy, and the mode never came on. I had the same concern though. I would add stabilizer to the Niro's tank if you don't plan on using the full tank within 3-4 months. There's really no harm in adding some "Sta-bil" using the recommended ratios (or even slightly conservative if the tank will be cycled in under a year). It's not just for motorcycles—works great in cars. Alternatively, you could fill up with ethanol-free gasoline if you have a station nearby that offers it. But adding stabilizer is generally cheaper.

 

[picstart]

Does anyone know if adding a stabilizer will violate the engine warranty?
Maybe the movement of the car under pure EV will agitate the gasoline and prevent the distillation of cetanes that occurs with gasoline stored in static tanks.

 

[yticolev]

You don't need an additive. Engine is direct injection, and the tank is pressurized. Nothing to gum up. Old carburetor cars and motorcycles on the other hand...

 

[dots]

@picstart, No, it shouldn't void warranties, nor is it mentioned in the manual. As an example, some fuels come with more additives than others. Car manufacturers don't say you can only fill up at Chevron or your warranty is void...

@yticolev, I agree there's no carburetor to foul up, but the fuel system is... a system (many components). Old gas can still leave deposits and impurities in gas lines, filters, or even fuel injectors. Buying top-tier gas can help, as they have better additives, but gas degradation is a gradual process. It doesn't just happen on day 86 or something. Granted, it might take a while to actually affect performance... just like high cholesterol may not become a problem for many years.

It'd be great if there were some tests done on fuel systems with 60/120/180 day old gas for x engine hours, and then a fuel system/engine teardown to view the effects.

 

[yticolev]

Gasoline can only leave deposits when it evaporates. In a closed system, that is incredibly minimal. Lawn mower stored for the winter? That is the other extreme. Pretty rare for an injector to get gummed up (if ever), especially direct injectors. Think about the pressures involved. Injectors are more likely to suffer from wear. There is nothing else that can get gummed up.

 

[dots]

I respectfully disagree that there's nothing else that can gum up, yticolev. Though my thoughts are really just my opinion. Here's another opinion on autoblog that discusses the effects of old gas:
https://www.autoblog.com/2008/03/31/does-gas-go-bad/

But yes, I doubt most will even need to worry about it.

 

[hawke]

I came across this article today but I still haven't found any similar information regarding Kia's PHEV. Since I own one it would be nice to know. My PHEV EX is almost three months old and I still have over a half tank of gas. Can't get myself to use gas unless I absolutely have to. It's become a new obsession of mine.

Plug-in Hybrids and Range-Extended EVs Need To Keep Your Fuel Fresh - Here's How They Do It | BestRide

 

[yticolev]

I didn't read anything in that ten year old article that changes my thoughts on modern design. If it appears in a manufacturer owners handbook, I'd probably still think it is boilerplate text from years ago that keeps getting copied. Urban myths hang around for decades.