Car is acting differently since trip

I haven't been able to get my car to go into stealth mode either when I start for work (sometime between 9 am and 12 noon, depending when I get up). I only have a 1 mile trip out of my subdivision, and then it's a four lane divided road to A1A. Therefore I can't benefit from stealth at all on starting off to work. (daytime driving SUCKS!).

I loaned my vehicle to my brother for a trip to SC and NE GA, and he averaged only 43.5 mpg, which seriously wrecked my low 50's I had. This hasn't affected the stealth mode, as I know it won't do this on start up anyhow (with the short trip out it won't warm up fast enough). All I need to do now is to check my air pressure in my tires in the AM (I haven't done so in the last couple weeks and it's been a month)

Keep testing, it may come back.....

 

Have you filled up and checked the mileage on your last tank since the long trip? Since you're getting more miles on the MFD average, it won't change as quickly as before, so you've got to overcome all the trip miles to bring up the average at all. You might be back to normal, or close to it, and it won't show up on the MFD unless you reset it.
(It will happen eventually, you know. You'll be cleaning the dust off the MFD or something and accidentally touch that button and <beep>, it's suddenly back to zero before you can blink...

Yes, that will make an effect, lowers the mileage (but cleans the exhaust).

I wonder if the computer 'learned' a new driving style based on the long drive. If that's the case it will slowly return to the other driving style, or you could disconnect the 12-volt battery and force it to lose it's memory (including radio presets, clock, whatever else might be in your package).

That's assuming the weather and tire pressure really is the same as before. Sounds like it went into stealth more easily than would be expected, although we're just finishing an unusually long winter here, so maybe I've forgotten what warm-weather driving is like.

 

Your probably just not entering stage 4.

 

Don't sweat the ethanol. It cleans the injectors and it burns cleaner.