Do I NEED to fill up every so often?

Sorry; your missing the whole point of this thread. Driving the car for 3 minutes is HV mode is even WORSE than staying in EV mode. Those short hops is dumping raw fuel and contaminating your engine oil even more. The motor needs to run long enough and hot enough to burn those contaminates out. Fuel will migrate out of the oil at relatively low temperatures, but moisture will require higher temperatures for a longer periods to be released from your motor oil. It's not just running the motor, just to run the motor - it needs to heat-up and burn out contaminates that accumulates in the motor oil. Moisture in the motor oil will encourage internal corrosion. Gasoline in motor oil will strip the adhesion properties of the motor oil to the smooth machined surfaces that it's suppose to protect. Lastly; it'll be hard on your CAT, since it needs to get up to a certain temperature to operate properly.

Hope this helps.....

 

What’s the rough door-to-door distance of the 3 minute drive? Speculating, considering average speed of 30 mph:

3/60 x 30 = 1.5 (miles).

^ Interesting, when I typed the above (in Safari on iPhone), it auto-completed the 1.5.

 

Just plug it in and drive it in EV mode for your short commute. Between your sister, fiance and concerts you should be driving enough long trips to burn through the gas way before it goes stale. Just don't fill it up all the way on your next fill-up. I keep my gas between 1/8 to 1/4 of a tank full. I usually add 1-3 gallons of gas every 1-2 months. Whenever you have an errand or social occasion that is 10-30 minutes away, you can just charge the car enough to comfortably get you there and use the HV mode for the way back. You may want to consider logging the days you use gas. You may be pleasantly surprised. I very rarely use gas for my commute for almost half of each year. However, I started tracking how often I used the engine and there wasn't any month I used it less than twice. As others have said, driving 3 minutes in HV mode regularly is probably worse for the engine than leaving the engine unused for a month or so.

If I lived that distance from a fiance and only drove to see them once a month or less, I think I would have bigger problems than my car.

 

If you drive a car for 3 minutes, you should think about selling it and buying a bicycle. It is more beneficial for your health, will help you lose weight, and your wallet will get fatter.