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Discussion Starter · #1 ·
Why is there no engine temp guage? or is this not a concern in the hybrid because of the engine cycling? :?:
 

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Ah, you have hit hyperion's hot button! He does have a temperature guage! :wink:

For better or worse, Toyota decided that on the Prius we would like to know the MPG at any given second, but not the engine temp, tach reading, oil pressure, or even whether the ICE is running. It has been the source for some serious gnashing of teeth on this forum.
 

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Heh. I like having a nice blank dashboard. It's tidy.

If the car does overheat, a symbol (and maybe a message) will come up on the display screen. I haven't ever heard of anyone on a Prius forum actually managing to overheat. I think it's only likely in the event of a coolant leak.
 

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If we had an engine temp gauge, we'd need to open up another REHAB center.
 

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Discussion Starter · #6 ·
hyperion said:
................. OH MY .........................
,,,,,,, ..... YOU DO HAVE THE IDIOT LIGHTS ....... ...........


I didn't want it to get to that point. I like to make things idiot proof.
but thanks for your input anyway. :?:
 

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The Prius is really meant to mask the driver from a lot of the minueta of how the vehicle operates, for better or worse. Since RPM is not related to ground speed or vehicle performance, it makes sense that a tach is not included on the dash, along with other gages which really don't mean as much on this vehicle as it would on others.

I was at greenhybrid.com the other day and an owner of an Escape Hybrid was complaining about high RPM when climbing a hill and that it "didn't seem correct". Well, if there were not tach on the dash of the Escape this poster wouldn't have had much concern.

All the rules of engine activity are basically broken with strong hybrids, so conventional gauges are also basically meaningless.
 

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jeromep has hit the nail on the head. Ignorance is bliss. Just look at the things people to when driving their cars with the battery indicator showing low on the MFD. Regardless of the lack of instructions in the Manual they will try using the "b" mode to over charge a low showing on the battery scale. Even might turn off their A/C to save battery charge. Imagine what you might do if you found what rpm your engine was turning at 80 MPH.
Can't even guess what you would do with a temperature guage flirting with the bottom of the red scale. Just wait for that idiot light and get a tow!
 

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For the first 100K miles, no gages are necessary. However, for those like me who keep cars for 200K+ miles, they can be important.

As the ICE wears and friction increases and compression lowers, it will have to work harder as well, so it will run hotter. Knowing the temp on an old mule is an important part of getting those last few thousand miles without a breakdown. Heading up a grade, it would be good to know when it gets hot enough that you would lighten the load (A/C, speed). The idiot light will just tell you to pull over NOW, whereas a light will tell you, "slow down or you'll have to pull over real soon."

On a new car it's more noise than signal, but on an old beast it can be very useful. I figure in ten years when I hit 200K I'll have found a scanner or system mod that shows me temp and oiol pressure when I want to see it.
 

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KTPhil said:
For the first 100K miles, no gages are necessary. However, for those like me who keep cars for 200K+ miles, they can be important.
Gauges are sometimes necessary in the first 100K miles as well!

I had an oldsmobile a while back, and I had taken it into an STS for service. THey did something and ended up loosening a coolant hose, which created a leak which got bigger as I drove.

In that car, the temperature gauge *never* moved off center when it was warmed up. When I saw it creeping up towards 3/4, yet still well below the warning area, I knew something was up. I got off the highway to pop the hood and check, and I saw the coolant tank was nearly dry.

That's the kind of thing that could happen to any car, and to any one. And that gauge kept the trouble to a minimum.

I honestly think the real reason we don't have gauges in addition to the MFMFD is the cost. It's a lot cheaper to put a simple digital display up on the dash than it is to put a real gauge cluster.
 

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The only criticism is that all this information is in the ECM and available to Toyota service with their scanning tool. Toyota could have made that all available to us with a simple button for the MFD as the Buick in my driveway will do. Allthough the Buick has both a coolant temp guage and an oil pressure guage, a tap of the engine info button will give you an exact reading of temp in degrees and an exact oil pressure.
 

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jeromep said:
. . .I was at greenhybrid.com the other day and an owner of an Escape Hybrid was complaining about high RPM when climbing a hill and that it "didn't seem correct". Well, if there were not tach on the dash of the Escape this poster wouldn't have had much concern.

All the rules of engine activity are basically broken with strong hybrids, so conventional gauges are also basically meaningless.
Actually, the Escape owner benefitted from the tach. He/she knew what question to ask on the board. Far too many new Prius owners have complained of loud engine noise in situations where they needed more power. They didn't even know what question to ask. But the still knew something was different about the Prius' behaviour.
 

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As for 'lightening of engine load', there hardly is any engine load, other than from the PSD, which would translate to road and generator.
The AC is electric, so it would not directly have a load on the engine.

Now another reason to have a coolant temp would be to detect a stuck thermostat. Twice on 2 different cars, I have found a stuck open thermostat, and was able to sense it when the engine stayed cold too long. Yes, I know, the ICE can cool when not being utilized, such as standing still, but I drive it enough that the engine should remain fairly hot during most of the trips.
My last car, a Saturn SL2, I was able to find the engine get too hot when the cooling fan quit. Car was fine as long as I kept moving, but when I crawled in accident traffic on a hot afternoon, I knew I had to escape and drive around a bit on side streets to cool things down.
 

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"The AC is electric, so it would not directly have a load on the engine. "

But where does that electricity come from? Maybe from the battery for a short while, but from the ICE originally. During a long climb (when you would be most concerned about overheating), the energy path is from ICE to gen to A/C, not a very efficient path. During those times, a temp gauge would be very useful.
 

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. . . All the rules of engine activity are basically broken with strong
. . . hybrids, so conventional gauges are also basically meaningless
.
Absolutely incorrect. They mean plenty, you just have to use a
different interpretation.
.
Having a tach and a battery-current meter probably
gained me about 15 mpg on average, after learning what they
could tell me.
.
Toyota really screwed the pooch by not including these BASICS
in the Prius.
.
_H*
 

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I could see where those would be useful. Attila has developed software that does just that using a CAN to RS232 (USB) and a sharp PDA.
 
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