2001 Prius start up

Yes, I have a 2001 Prius and that is normal. The 2001 (Classic Prius) does not have the hot water tank that allows the 2004-2007 Prius's (HSD Prius) to start driving without starting the engine. The 2001 needs to run the engine to warmup and get to a low pollution condition of a warm engine quickly so it will always start the engine after being off for a while.

Just as a small note, the 2001 will show the over/under temperature indicator (little thermometer) on the dash when warming up. This little thermometer indicator is an overtemp indicator on the HSD Prius and usually does not show up.

 

<div class='quotetop'>QUOTE(Kipper @ Jun 24 2007, 08:57 PM) [snapback]467418[/snapback]</div>

Welcome to the site. Sounds normal. The engine needs to heat the catalytic converter so it runs for some time when started.

 

You'll find that sometimes when you start it, the motor won't come on right away, even if you've let it sit around for awhile, whereas other times you can be just hopping back in it right after driving it, and the motor will run. For this reason, I don't think it has as much to do with warming up the car as it does with the Prius being happy with the amount of charge on the battery. This was likely nothing more than a software tweak with the Prius II.

As far as I know, the Classic Prius DOES keep heated coolant and injects it into the engine just as the newer one does. But remember that this just reduces warm-up time, it doesn't eliminate it altogether.

In any case, don't worry, the Prius knows what it is doing.

In spite of this slightly different behavior with the Classic Prius, the MPG over the first five minutes of driving it is about the same as with the HSD Prius.

 

You'll find that sometimes when you start it, the motor won't come on right away, even if you've let it sit around for awhile, whereas other times you can be just hopping back in it right after driving it, and the motor will run. For this reason, I don't think it has as much to do with warming up the car as it does with the Prius being happy with the amount of charge on the battery. This was likely nothing more than a software tweak with the Prius II.

As far as I know, the Classic Prius DOES keep heated coolant and injects it into the engine just as the newer one does. But remember that this just reduces warm-up time, it doesn't eliminate it altogether.

In any case, don't worry, the Prius knows what it is doing.

In spite of this slightly different behavior with the Classic Prius, the MPG over the first five minutes of driving it is about the same as with the HSD Prius.

 

the NHW11 prius does not have a heated coolant storage tank, it is just like a normal car when it comes to engine cooling.

the 2001 prius on startup will start up the gasoline engine to charge HV battery, unless vehicle is warmed up already, the engine will lower revs and turn off. If the battery is up to charge but engine isnt warmed up the engine will run until it has warmed up, then lower revs and turn off.

 

<div class='quotetop'>QUOTE(statultra @ Jun 25 2007, 09:24 AM) [snapback]467566[/snapback]</div>

I'm sorry, but that doesn't wash with my experience of being a Classic Prius owner. Whether or not the engine starts when you first turn the car on seems purely related to the battery charge, not if the engine is warm.

If you re-read what I said, many times the engine will start when it is clearly warmed up, and other times it won't start even if I have had the car parked for a few days. However, about 80% of the time, it does start.

The HSD Prius not starting the engine by design is clearly just a software tweak. If you do some research, you'll find articles talking about the 'superheated coolant' tank existing on the Classic as well. Although, I do believe that the tank was much smaller on the Classic.

 

Don't know what kind of Classic Prius you've been driving, but mine *always* starts the gas engine when you turn the key.. *IF* you have recently run the car and the system is still hot, it will shut off in about 30 seconds. The only other situation I've come across where the engine will shut off is if you immediately shift into *reverse* and the battery is high, it will shut off, but in such a case, unless the system is hot, the moment you shift back into drive, the engine will immediately start up again.

I've got a Miniscanner and can see the battery SoC, and for various reasons, I've experimented with force charged the battery up over 80%, which is normally not possible under standard operating conditions, and even this extremely high SoC does *NOT* stop the engine upon start-up..

The gas engine my Classic *always* starts (it was done this way so that people switching over from a conventional vehicle would find the system familiar: turn key, engine starts. If I recall in "The Prius That Shook the World", it was stated that the original prototypes did not necessarily start the engine and that the reason for the change was as stated); it may shut down quickly if the system is already hot, but there is no situation in a Classic where you can turn the key and get a Ready light without the gas engine running at least momentarily.. How long the gas engine runs is dependent on system temperature (and perhaps, living in Austin TX, the ambient temperatures in your locale is enough keep the system hot enough between drives so that the system can shut down early, but it's certainly *NOT* the case in more temperate climates..)

Lastly, for the record, the Classic Prius does *NOT* have any kind of themos for engine coolant..

 

being the owner of 2 classic prius's, i know the operation both in summer and winter, the engine start stop operation is dependant on battery charge, but also upon engine temperature, if the engine coolant temperature is not sufficent the engine will not shut off until it has fully warmed up. On the NHW20 prius the system works a bit different. The Toyota Hybrid System on the classic prius ALWAYS starts up the gasoline engine, regardless if its warmed up or not or sitting for a few days. Also being a mechanic that fixes Prius's ( Created a HV charger removed inverters and worked on gasoline engine, especially on cooling system 01-03 and 04-07 ) the classic prius DOES NOT have a superheated coolant tank of any type.