Excessive/Ghost Mileage after mechanic?

Yes 67 days.

 

After Bisco's message and this report from toyota, I went looking at some other videos out of curiosity.
I found a Toyota demo with the exact same behavior as mine. Here is the cut/zoomed in version.

I'd like to formally apologize and thank everyone who's helped me in this thread.

The only explanation I can think of is I went 6,000km/90 days somehow not seeing this behavior, and started paying more attention after an expensive mechanic visit?

It's not a sufficient explanation, because even with all this evidence I'm near certain this didn't use to happen, at least often enough for me to notice. But what can I do?

Once again, thank you and sorry.

 

TIPS FOR ANYONE VIEWING THIS THREAD IN THE FUTURE:

• ABOVE ALL ELSE, if you notice the MPG drop/LPKM skyrocket when the engine is activated (around 20-40km/h) THIS IS NORMAL. THIS IS INTENDED BEHAVIOR.
• If you stay below the ICE threshold, then go above it, then let your foot off the pedal below the ICE threshold (but not all the way off the pedal!) It will continue using the engine. This is intentional. I suspect this is to avoid inefficient engine startups (<3 seconds of the engine being on). If you want to force it to use electric again, let your foot ALL the way off the pedal long enough for the L/KM to drop to 0 (or MPG to rise to 100) and accelerate again.
  

• When your brakes are being replaced, the mechanic may have some problems with the parking brake as it can be very difficult to do. To ensure its not dragging, lifting the car up and giving a good push to the wheel should yield 1-2 turns.
• If you connect an ODB2 reader, the throttle will typically sit at 15%. This is normal. Revving up to 2000 rpm and load increasing to 90% when the engine turns activates is also normal.
• If your engine keeps turning on randomly/frequently despite your hybrid battery being above 2 bars, check your 12V. If its been sitting around for 5-6 years, definitely consider replacing it if this is a concern for you. If its not, simply get it tested somewhere. But CCA is not entirely important for the Prius, keep that in mind if its a little low.
• See Mendel's post for a comprehensive list of maintenance requirements. Excessive/Ghost Mileage after mechanic? | Page 3 | PriusChat
• If you want to clean your fuel injectors (with additives), use MotoMaster F1 Extra-Strength Fuel Injector Cleaner. Mendel did the math, add in 2.81, or 3 oz to a fuel tank of fuel (45L). Be careful not to use cheap brands or overdo the injector cleaner by a lot: It could screw up the charcoal canister.
• Speaking of charcoal canister, some people have reported theirs breaking from overfilling at the gas pump. This is mostly unlikely, but if you want to be safe, just fill up until you hear one click, and thats it, don't push it. Whats that extra dribble afterwards going to do for you anyway?
• If you have an issue with your EVAP/Purge system, do a full check on your own first if you can. Common cause can usually just be a gas cap. In rare cases, see these two posts for a description of how a faulty purge valve can cause many, many problems.
  unexplained engine racing | PriusChat
  Engine behaving strangely and popping hoses off intake manifold | Page 2 | PriusChat
  
• DON'T SNAP YOUR BOLTS. Just take it easy with that ratchet!
• This is to any non-diyers. Trust me when I say it's a very valuable and rewarding experience to clean out your EGR system. Mechanics price it very high, but if you put in a little bit of effort and watch NutzAboutBoltz's videos, there's no uncertainty.
• Oxiclean is arguably much better than any brake/carb cleaner. In my experience, at least.
• Don't take such a helpful community for granted!

Please let me know if anything is incorrect or I missed anything important.