why no oil pressure, water temp gauges

[ahernj@sbcglobal.net]

As part of my normal driving pattern I am constantly looking for the maintenance gauges, they are not there, and I miss them. Does anyone know why no gauges?

[Jiipa]

What would you do when you're driving along at 35 mph, the ICE shuts off and your oil pressure drops to zero?

[diamondlarry]

Originally Posted by Jiipa

What would you do when you're driving along at 35 mph, the ICE shuts off and your oil pressure drops to zero?

That's a valid answer for when you are in slow speed traffic but what about when you are cruisin' down the highway at 55+ and the oil pressure drops to 0? And, at any speed, what about if a hose pops and you lose all your coolant and start to overheat? I too found it odd that there were no gauges/idiot lights of any kind. This is the first car I've ever had that's not had gauges.

[hobbit]

Nobody really knows why Toyota chose to install so few good
diagnostics in the Prius, other than the theory that they wanted
to make it *simple* for the then-new community of owners who
were still a little leery of "hybrid technology". Since then,
some of us who have installed instrumentation find it absolutely
essential, and others still don't care one way or the other.
[But most of the non-owners I talk to are still amazed that it
doesn't come with a tach.] Lack of instrumentation and lack
of a good understanding on how the system works is probably why
the original 60/52 EPA numbers were so low when the car is
capable of much better than that, properly driven. And now of
course the numbers are even lower than that.
.
They could have done a whole lot for the gauge-addicts with just
a little more programming for the screen display, and the folks
who didn't care about that stuff could simply choose to not
bring up the appropriate menus. But they didn't, which some of
us took as a challenge.
.
_H*

[Fraser]

Originally Posted by hobbit

But most of the non-owners I talk to are still amazed that it doesn't come with a tach.

Not being technically proficient, I'm wondering whether a tach would function properly, if at all, if the battery were doing the propulsion. Extending that thought, would it be accurate if the battery were helping the ICE.

[richard schumacher]

A monster instrumentation selection for the MFD would be awesome.

A tach works just fine: when the engine isn't turning it reads zero :_> Would you want the tach to indicate engine RPMs when the engine is spinning but not delivering any power?

[dogfriend]

Originally Posted by richard schumacher

Would you want the tach to indicate engine RPMs when the engine is spinning but not delivering any power?

Actually, if you have a ScanGauge, the tach does report the engine RPM when the engine is spinning because you are over the 41 mph transition speed. I also monitor fuel flow (gal/hr) and you often see ~960 rpm with 0 gal/hr.

I use the ScanGauge to add: tach, engine coolant temp, ignition advance, fuel flow.

[Ogo]

All those gauges are cool, but basically not essential at all in car like Prius, where 99% of things are automatically controlled.
Regarding low oil pressure, high engine temperature and similar things, appropriate warning lights will turn on, when things go bad anyway, so no need to worry about it.

[jpadc]

But its actually a little worse than no gauges, because what Toyota supplies is misleading. The power indicator gauge can show that only the EV is applying power, but that does not mean then ICE is not running. A tach would have at least made the truth about that clear. Its why I want a ScanGauge too, but I'd like one that was built into the Toyota display screen. The have add-ons that display my iPod on the tuch screen, how about one for a ScanGauge type device!

[hobbit]

Oh right, forgot to add that there's no oil pressure sensor that
actually gives a pressure figure, just a switch that grounds
when it's too low.
.
I'd say the most important gauges I use while driving are the
tach and the battery-current meter. The tach does go to 0 when
the engine is stopped or is being spun in fuel-cut mode, because
the tach comes off the ignition system. In the case of the Prius
the tach can also indicate engine load to a degree, but you have to
know where the sweet-spot ranges are. For that I've got a vacuum
gauge and more recently have taken to watching fuel-injector time
on the SG.
.
So you see that much of the instrumentation you want can be
had in a variety of ways, you just have to DIY...
.
_H*