[Michael F. Holahan]

Whomever:
I will eventually get a Prius but dealers in my part of Florida seem to have no interest in selling them. I have only been able to look at one once...six months ago. The brochure doesn't show any readouts for engine temperature and oil pressure etc. Being a former pilot, these things are important to me. I like the Prius for it's hatchback configuration but I wish it had instrumentation more like the Civic hybrid.
M. Holahan.[/i]

 

[SkipHuffman]

Whomever:
I will eventually get a Prius but dealers in my part of Florida seem to have no interest in selling them. I have only been able to look at one once...six months ago. The brochure doesn't show any readouts for engine temperature and oil pressure etc. Being a former pilot, these things are important to me. I like the Prius for it's hatchback configuration but I wish it had instrumentation more like the Civic hybrid.
M. Holahan.[/i]

I can understand the desire for more engine information, but with the computer controlled system that information may be more confusing than useful.

Imagine this scenerio. Your are tooling down the highway at 65MPH. Suddenly your oil pressure drops to near zero.

As a pilot your reaction is likely to be "Ack! I am losing an engine! Throttle back, feather prop and start looking for a nice smooth cornfield."

In the prius this reaction is dead wrong. What happened is that the highway has begun a long gentle downgrade, probably one that you cannot even detect, and the ICE has shut off.

When the road levels out again, or starts a gentle upgrade, the ICE starts back up and the oil pressure climbs back to where it belongs.

As the driver you never need to be aware of these things, they are more likely to confuse than clarify.

 

[zinzindorff9]

Mike,I totally agree but I've discovered that most of Prius purchasers will disagree with your assumptions. I can't believe there isn't a "after-market Tach and set of temp guages available or that Toyota failed to add it to the "info" screen. Seems as though most Prius buyers are content to drive their cars until a red light appears on the dash and then call and have it towed to a dealer. The engine is another factor since it is not a normal internal combustion engine and could not operate the car by itself without the aid of the two electric motors. It is an "atkinson" cycle engine and although rated for 80 hp only puts out 45 hp and relies on the electrics for the additional torque nesessary and is limited to 4500 rpm. It is a mechanical marvel but since the rpm has little to do with power output the tach isn't all that necessary since all you would be using it for is indication that engine is running. The thing has to spin up to 1,000 rpm by the smaller of the two electric motors before fuel is supplied to two of the four cylinders for "every" start. There is an aftermarket "light" modification somewhere that will give you this info. The Prius screen will not do this and only shows engine operation when it is supplying some sort of power, whether it is to run car or charge battery. Sometimes, it just "runs". (To heat catalytic converter, heat engine coolant etc I hate this lack of instrumentation but have found replies to this question by owners that either they never looked at them in their previous cars or that their previous Japanese cars did not have them and they weren't missed. I think there is a different type of buyer for the Prius and not the Corvette or sportscar owner of the past. These things are years ahead of the industry and I just wish buyers were a little more demanding. As far as I know, in the northeast there has never been a demonstrator on the floor of any dealer since the 2004's hit the street. My dealer knew very little about the car or how "it worked" and could only give me a test drive in a new Camry as he said they drove identically. The dealers just don't get enough to take an interest unless they are part of the few who insist on sinfully high "markups. Those guys all have a lot of "demonstrators" There is a lot of info out there but not at a dealer. You have to dig for it and even with it's shortcomings it is a fantastic machine. Toyota priced it at market value and to keep it there had to dispense with a lot of things you would probably like in your car to make it perfect. As long as you "play the game" and get your car at MSRP from a reputable dealer you are getting your moneys worth and more. I think if you foolishly pay more than list you'll be kicking yourself in the butt at this time next year when the supply has caught up! About oil pressure dropping off when "coasting" A tachometer would indicate why, and an engine operating light would be indicating off. If you are any way mechanically aware all this info would be of much more value than variable fuel present consumption figures displayed on a graph. And as far as temp. The Prius has two separate cooling systems. One for the "ICE" and the other for cooling the electrical inverter. Both critical and a loss of any coolant in these systems would first become obvious by a rise in temp guage well before the red light and steam from under the hood. And by the way Mike, I don't think you would be at all happy with the Civic. The internal combustion engine in it is a four cylinder, eight valve engine vs the Prius all aluminum block four, with double overhead camshafts and 16 valves.

 

[ken1784]

Imagine this scenerio. Your are tooling down the highway at 65MPH. Suddenly your oil pressure drops to near zero.

If this happened, something is wrong with your Prius.

In the prius this reaction is dead wrong. What happened is that the highway has begun a long gentle downgrade, probably one that you cannot even detect, and the ICE has shut off.

Please note that the ICE is always running and supplying oil presure at the speed 42MPH and above.

Regards,
[email protected]

 

[SkipHuffman]

Imagine this scenerio. Your are tooling down the highway at 65MPH. Suddenly your oil pressure drops to near zero.

If this happened, something is wrong with your Prius.

In the prius this reaction is dead wrong. What happened is that the highway has begun a long gentle downgrade, probably one that you cannot even detect, and the ICE has shut off.

Please note that the ICE is always running and supplying oil presure at the speed 42MPH and above.

Regards,
[email protected]

Perhaps that is true on the 2001, but I have seen my 2004 go to 100MPG on the highway at a constant speed going down a slight downgrade. (Briefly.)

But either way, change the constant speed in my first post from 65 to 41. And the freeway to a country road.

The point is the same. Oil pressure is an incomplete indicator of system health in a Prius.

 

[ken1784]

Perhaps that is true on the 2001, but I have seen my 2004 go to 100MPG on the highway at a constant speed going down a slight downgrade. (Briefly.)

The 100MPG only shows Prius is running in fuel cut mode.
I drive 2004 Prius with a tacho-meter, so I'm sure it is true.

Regards,
[email protected]

 

[RSnyder]

Mike,I totally agree but I've discovered that most of Prius purchasers will disagree with your assumptions. I can't believe there isn't a "after-market Tach and set of temp guages available or that Toyota failed to add it to the "info" screen. Seems as though most Prius buyers are content to drive their cars until a red light appears on the dash and then call and have it towed to a dealer.

I don't think that's really true for most Prius owners, there's just not a good option available at the moment.

There are after-market Tachs available that will work with the Prius. They pick up the spark plug signal, so might not work during fuel cut above 42 MPH (engine spinning, but no fuel). Is spark also cut?

For the rest of the instrumentation, there is a group of people working on decoding signals on the 'CAN' bus. Hopefully, they will be successful soon and announce something. For older 2001-03 Prius, there's Graham's miniscanner (normally available from Ecros tech, but they're currently out of stock).

The engine is another factor since it is not a normal internal combustion engine and could not operate the car by itself without the aid of the two electric motors.

You make it sound like a big deal, yet there is no mass market car available with an engine that can operate the car without the aid of a transmission. The Prius has an unusual transmission with two large motor/generators, but it's still a transmission.

It is an "atkinson" cycle engine and although rated for 80 hp only puts out 45 hp and relies on the electrics for the additional torque nesessary and is limited to 4500 rpm.

Rated for, and puts out 76 HP at 5000 rpm. Power from the battery adds to this.

It is a mechanical marvel but since the rpm has little to do with power output the tach isn't all that necessary since all you would be using it for is indication that engine is running.

RPM is highly correlated with power output. Unlike traditional cars, it's not particularly correlated with vehicle speed.

The thing has to spin up to 1,000 rpm by the smaller of the two electric motors before fuel is supplied to two of the four cylinders for "every" start. There is an aftermarket "light" modification somewhere that will give you this info. The Prius screen will not do this and only shows engine operation when it is supplying some sort of power, whether it is to run car or charge battery. Sometimes, it just "runs". (To heat catalytic converter, heat engine coolant etc I hate this lack of instrumentation but have found replies to this question by owners that either they never looked at them in their previous cars or that their previous Japanese cars did not have them and they weren't missed. I think there is a different type of buyer for the Prius and not the Corvette or sportscar owner of the past.

Again, there are quite a few owners interested in instrumentation of their Prius. It's not currently available, but stay tuned...

These things are years ahead of the industry and I just wish buyers were a little more demanding.

Sadly, it's tough to be demanding when supply is very limited and competition is close to non-existent. Hopefully, things will improve as supply problems ease and more manufacturers offer products.

As far as I know, in the northeast there has never been a demonstrator on the floor of any dealer since the 2004's hit the street. My dealer knew very little about the car or how "it worked" and could only give me a test drive in a new Camry as he said they drove identically. The dealers just don't get enough to take an interest unless they are part of the few who insist on sinfully high "markups. Those guys all have a lot of "demonstrators" There is a lot of info out there but not at a dealer. You have to dig for it and even with it's shortcomings it is a fantastic machine. Toyota priced it at market value and to keep it there had to dispense with a lot of things you would probably like in your car to make it perfect. As long as you "play the game" and get your car at MSRP from a reputable dealer you are getting your moneys worth and more. I think if you foolishly pay more than list you'll be kicking yourself in the butt at this time next year when the supply has caught up!

I hope you're right. Hard to predict though.

About oil pressure dropping off when "coasting" A tachometer would indicate why, and an engine operating light would be indicating off. If you are any way mechanically aware all this info would be of much more value than variable fuel present consumption figures displayed on a graph. And as far as temp. The Prius has two separate cooling systems. One for the "ICE" and the other for cooling the electrical inverter. Both critical and a loss of any coolant in these systems would first become obvious by a rise in temp guage well before the red light and steam from under the hood.

If they implemented the red light properly, it should shine at least as soon as you would detect the problem on a temperature gauge. Both well before steam. By the way, the temperature gauge on the 2001-03 miniscanner tends to be boringly steady at 83-85 deg. C once the engine warms up, unless you do a lot of stealth.

And by the way Mike, I don't think you would be at all happy with the Civic. The internal combustion engine in it is a four cylinder, eight valve engine vs the Prius all aluminum block four, with double overhead camshafts and 16 valves.

I haven't tried the HCH, but Honda has a good reputation with engines.

 

[ehurtley]

On a similar freeway 'slight downhill stretch', I have witnessed two Energy screen oddities.

1. The screen showed that I was running solely on battery power. Yellow lines going from battery to motor to wheels. If I shifted to 'N' (or just feathered to neutral,) the car would slowly decelerate, yet if I applied gas carefully, I could accelerate 1-2 mph on what the screen said was only electric power. (Hrm, I guess 'applied gas' isn't really appropriate then, is it?)

2. On the exact same stretch of road (I-5 Southbound, about 10 miles South of Portland,) I have had the display saying that I was using only gas power to maintain speed, with no energy going to the electric motor (either to help power the wheels, or charge the battery,) yet it said my mileage was 99.9 MPG. So it is possible to use the ICE, yet still get a 'max' reading.

This is an odd stretch of road, in that in my other (manual transmission) car, if I purely coast, I will hold 55 mph. In the Prius, it will coast in N at 57 mph (better aerodynamics, I'm assuming,) and I can get up to as much as 62 mph on battery power alone, according to the display. Sometimes it seems to only use battery to do this, others it uses gas, but gets 99.9 MPG. (This stretch is about 3 miles long, perfectly straight, and in my other car, I can hold a perfect 55 mph in neutral for the entire 3 mile stretch. The speed limit here is 55 for the first mile, 65 for the other two. It's three lanes, and I tend to go 'slow' in the right lane to stay out of the way of the rest of traffic that averages 70.)

 

[zinzindorff9]

Would it be fair to say that because of the multitude of variables it would only be possible to determine that the "ICE" was really "running" would be with an "engine running" light. And has anyone manufactured one of these for the 2004 Prius?

 

[Guest]

And has anyone manufactured one of these for the 2004 Prius?

http://priusdiy.fc2web.com/

Sorry, it is Japanese only.
Hope Babel Fish will help you for translation.

Regards,
[email protected]

 

[efusco]

Would it be fair to say that because of the multitude of variables it would only be possible to determine that the "ICE" was really "running" would be with an "engine running" light. And has anyone manufactured one of these for the 2004 Prius?

Coming soon from Coastaletech...includes a brake light too so you can tell when you're just using regen braking vs friction braking...

http://coastaletech.com/new_page_1.htm

 

[ken1784]

There are after-market Tachs available that will work with the Prius. They pick up the spark plug signal, so might not work during fuel cut above 42 MPH (engine spinning, but no fuel). Is spark also cut?

You don't have to pick up the signal from the spark plug.
There is an ICE running signal at pin#9 on the DLC3 connector underneath the steering wheel.

Regards,
[email protected]

 

[zinzindorff9]

Ken, Is there a kit yet for an indicator light indicating "ICE" is on? Coastal Dave is coming up with a kit of some sort but his kit when availaible will also show "regenerative braking" which I am not interested in.

 

[ken1784]

Ken, Is there a kit yet for an indicator light indicating "ICE" is on?

Hello,

I made it by myself.
I'm going to introduce it at my DIY site but it"ll happen in a few months.
An alternative solution is...
Get a Digital Multi Meter which has 12V pulse frequency measurement capability, then connect it to the pin#9 of DLC3 connector.

Coastal Dave is coming up with a kit of some sort but his kit when availaible will also show "regenerative braking" which I am not interested in.

I believe his kit is for the friction brake indicator.

Regards,
[email protected]

 

[zinzindorff9]

Ken, if you now check out http://www.coastaletech.com you will find a picture of the soon to be made indicator. Looks like a four by two inch box to be mounted in the cavity of the small left front window. It will indicate regenerative braking and "ICE" running light. I would like to see just a small one light bulb for the "ICE" The rest is completely unnecessary info to me.

 

[ken1784]

Ken, if you now check out http://www.coastaletech.com you will find a picture of the soon to be made indicator. Looks like a four by two inch box to be mounted in the cavity of the small left front window. It will indicate regenerative braking and "ICE" running light.

Visited http://www.coastaletech.com/new_page_1.htm
Found...
"This unit visually displays relative amount of friction braking which is being applied"

I would like to see just a small one light bulb for the "ICE" The rest is completely unnecessary info to me.

So, you are looking for something like...
http://priusdiy.fc2web.com/ICE_monitor.html

Regards,
[email protected]

 

[zinzindorff9]

OK, What the heck am I looking at? Looks like "Greek" to me

 

[zinzindorff9]

The way I interpreted coastaletech's web page, this unit falls under category "Brake/Engine Run" Then states "instantaneous indication when engine STARTS. You believe that means it is not always "ON" when "ICE" is running? And if it is possible to find the correct "Pin" location would it power a 12 V bulb or a 110 V bulb?

 

[kenmce]

>Michael F. Holahan
>The brochure doesn't show any readouts for engine temperature and oil >pressure etc. Being a former pilot, these things are important to me. I
>like the Prius for it's hatchback configuration but I wish it had
>instrumentation more like the Civic hybrid.

I think they were afraid people would drive around hitting buttons and watching the MFD instead of driving the car. If you want proper instruments you have to add them yourself.

 

[zinzindorff9]

Aw Ken, If we but could, I'de swap the MFD for a set of normal instruments and be happy to drive my car like a normal one which it is, and which Toyota would like us to condider it is. So far no instruments are available. Standard car tachs can't be used as all the engine instrumentation comes out of a computer which "knows" but won't tell! The MFD will not even tell you when the "ICE" is operating at all times.