Insane City MPG

Yea the rear tires are original and almost bald and the fronts are new but some off brand. I do have the 17 inch wheels.

 

Hi Ski
There's a lot of things that can happen to a car in 50k miles that can effect efficiency. If you have the cars lifetime mpg that can tell a lot about the previous 50k miles driven. Even, just a few little things that are barely noticeable can add up and kick butt on 40-50 mpgs. Things what would never be noticeable in a car that typically gets 20-30 mpgs. Knowing the cars history can tell a lot, but here at PC most of us can only guess why there's such a big difference between the two cars you compared.

 

About mpg, I concur with others. Yeah, tires and wheels are most likely. Also, the dash indicated mpg may be off by different amounts. I don't know about regular Gen4, but for Prius Prime, 2017 had an average 6.02% optimistic display than hand calculated mpg while my new 2021PP shows an average 8.69% better number on the dash. (But my number on the filling on the 2021 is still very small, so it may not be a statistically significant difference.

As for the LTA (lane tracing assist) function on the 2021 Prius, it is based on the TSS2.0 whereas your 2016 has only TSS1.0 with LDA (Lane Departure Alert) with steering assist. LKA (lane keep assist) was not part of the TSS1.0. The TSS2.0 LTA vastly improved upon the early TSS1.0 LDA with steering assist. TSS2.0 DRCC is also a full range while TSS1.0 was not.

 

OK, it was a "full range" in TSS-P. But in my 2017 PP, the DRCC did come to a full stop but I think with some warning light? and to reengage, it had to have a tap on the gas pedal to resume. For my 2021PP, the DRCC does not show any warning and I don't have to tap on the gas pedal after coming to a full stop.

Here is what I found in the Toyota brochures. The TSS-P brochure is labeld AUG 2018 but I think it is TSS-P 1.0. The TSS 2.0 brochure is also labeled AUG 2018, but it must be when the new version of TSS was introduced. Looks like TSS2.0 allows to engage DRR at 7mph slower speed. One question, for those cars with non-full-speed DRCC, the operation speed range was 25mph for TSS1.0 and 15mph for TSS2.0, but if the car is on non-full-range DRR and a car front of it comes to a full-stop, at speed below 15mph, what happens? I can see PCS will prevent the collision, but DRR is automatically canceled below 15mph (on TSS2.) or 25mph (on TSS1)?

On any of my old standard cruise control, it would not cancel but will be kept going at the set speed. So, even non-full-range

TSS-P

TSS 2.0