Engine temperature gauge and tachometer

There are a number of aftermarket ways to get more gauges:

1) I use a scangauge II, it can display 4 of about 100 different gauges; I currently show RPMs, Coolant Temp in F, Intake Air Temp in F, and instant MPG, as those interest me. It may be a while before folks find all the possible gauges for the Prime. It is also an OBDII programmer, and a diagnostic scanner. If you need more than 4 gauges at once they can be daisy chained. ScanGauge II ODB Scan Tool + Digital Gauges + Trip Computers - PriusChat Shop

2) If you have a 'spare' Android device and an OBDII to Bluetooth transmitter, you can run the Torque software Torque — OBD2 Performance and Diagnostics for your Vehicle It has similar features, but allows and requires more customization on your part.

There are undoubtedly others, but those I have used.

 

so, no, no temp or tach. but your info says you have a prime, are you just wondering if you can't find them in the myriad of displays?

 

Engine coolant temp in the dash would be very nice, no idea why they don't have it.

 

I have had a Gen 2 and now a v, but not a Gen 4 or Prime, so this is true for me, and I have no reason to suspect it is not true for you:

The CVT really works, there is no link between RPM and speed, or pedal position. The computer picks the RPM it thinks best suits the conditions. 60 MPH might be 1400 to 2400 RPM on the level. (battery charge, temperature, wind speed and direction, precipitation all change RPMs even on the level. Elevation changes alter it even more.)
Redline for my v seems to be 5200, (the Gen 2 was 5000) mostly going up hill at highway speeds.

The CVT does an odd overdrive, called heretical mode, to lower RPMs and increase throttle opening so the throttle plate is fully open and not blocking air flow. (so it lowers pumping losses, similar to a diesel) So I see the engine running at the efficient RPMs even under full throttle. The low point is the most efficient range. (this compares Gen 2 to Gen 3)

Heretical mode makes Motor/Generator1 a motor and uses M/G2 as a generator. Normally M/G1 is the generator and M/G2 is a motor. In Heretical mode, the engine can push against M/G1, slowing it down while still allowing full throttle.

Again, when going uphill, you do run closer to redline.

 

you know the engine has finished the warm up cycle when it shuts off if you lift your foot off the accelerator.
what are you trying to accomplish with rpm's?

 

RPM never interested me that much, when I was using SG. Maybe to see what happens when the car is showing no fuel being consumed, at highway speeds (it's still doing idle speed).

Coolant temp was always of interest though.

 

All my previous cars were manuals, so I was used to being in control of RPM. I am slowly getting used to the computers doing the right thing.
Coolant temp interests me, but in my Gen 2, air temp seemed to get 'too high' in the summer and MPG seemed to go back down. I see no sign of that in the V; the more warmed up it gets, the better it goes.

 

I just got my Prime and was wondering that too - that's the gauge I've always used to determine when to turn on the heat.

 

New to prime here in (sometimes) frigid New England. How do I know when the engine is warm enough to turn on the heat without getting nothing but cold air blowing out? I used to go by the temperature gauge.

 

I do not own a Prime, but both my Prius waited until there was warmth, before running the fan. (on Auto) Have you tried setting the temp you want on Auto and watching what the Prime does? If you never have to think about comfort again, that leaves more attention for traffic.

 

Recall driving my daughter-in-law's Sunfire over to Costco (for a flat repair), and muttering: "even this heap has a temp gauge".

 

I can confirm that on the climate set to auto and a reasonable temperature set, you don't get blasted with cold air. There is some air movement as the car pushes the ever warming air through the sensors to detect if it is at temperature but for the most part the car does a good job of providing you with the right temperature air.

 

The heating is supplied by a heat pump and so does not use/need the engine. You can preheat the car by pressing the a/c button on the remote control from outside the car which remains locked. The engine does not run but the heat pump fan can be heard running on mine for about 10 minutes. This may need to be repeated to totally defrost the exterior and warm the interior. If you do this while plugged in it will not deplete the battery range[mine remains at 57km].The heating turns off when a door is opened. When driving and using the engine the heat pump collects heat from the exhaust system to save battery power. When I turn on the heating while driving the indicated range drops by 3 km but returns these 3km if I turn off the heating.

 

The heat pump only works down to a certain temperature. Although low, mornings in New England can be below that. During those times, it nice to be able to monitor engine temperatures in some manor. Better to leave the fans off while the engine is still heating the coolant up than having cold air blow over the heater core.

 

Vehicle computers will ramp up fans at appropriate engine/coolant temps if climate system is set to Auto and front defroster is off.

 

Yet some prefer to have no air going over the heater core if they won't provide heat.

The ECU is monitoring the coolant temperature. It should be easy to display it on some screen.

 

My scangauge II displays RPM, instant MPG, intake air temp*, and coolant temp, as my preferred gauges.

* my Gen 2 intake air temp, climbed sharply if the outside temp was over 95, to 115. My v does not spike as bad.

 

My scanguage got into the habit of also displaying "check hybrid system" on the dash. It's a GREAT work around, but if there's some way of putting coolant temp on Toyota's to do list, I'd love to do that.

Their attitude seems to be "don't worry your little head about things like that, enjoy your infotainment, look at all the pretty lights"...