Used an engine diagnostic tool to check RPM of my Prime

The driving modes only change the pedal mapping. Toyota published this.

EV Mode: Separate ECO, Power, and Normal Modes? | PriusChat

 

My Energi allows for a custom display of which RPM and a coolant gauge are some of the selectable options.

I use a Scangauge II in the Prius for seeing RPM and temps.

 

I'm curious what the RPM is when the engine first comes on (warm-up period) and when it is warmed up and you're cruising along at a fairly low speed. Do you happen to know those numbers (approximate)?

 

Engines are typically more efficient with NORMAL RPM and higher LOAD. This is how most vehicles are getting better highway mileage. I recall cars in 80’s running at 2500 3000 rpm on the highway at 65-70. Today my 2013 Jeep Wrangler is sitting just under 2000 RPM at 65. My 2001 Wrangler spun at 2800 on the highway and used much more fuel to maintain 65. Remember the fuel used not only gets output for pushing the vehicle it also gets used to: pump oil, rotate crankshaft, move pistons, actuate valves etc. this all as a scavenging cost to the fuel economy. Faster movement of all these pieces reduces economy. If the load is matched at a lower RPM and with the smallest sized components as possible economy is increased. If you had the grams/HP*H, the steady flat road speed of the vehicle, RPM of engine and the current being pushed to the battery we could really look at where efficiency is gained in this hybrid setup!

 

I have a ScanGauge II connected all the time, and RPM is one of the four things I choose to watch. (also instant MPG 0:9999, avgMPG 0:9999 and engine temp. There are around 16 things you can choose to monitor in the 4 available spots. With an upgrade (which I haven't had done, as you have to send it back) you can also monitor (like Camrys!!!) the individual tire pressures! This is maybe 2.5" wide and 1" tall (est). and sits on top (with double back tape) on the top of my steering column.

 

For the Prius Prime, are you able to get error codes with your scanner? With my scanner, I am not. Thanks.