Engine starting at power up

My 2010 starts the engine about 10 seconds after hitting the Power button. The Prius' first function in life is emissions first and gas mileage second. So, the Prius will start the engine to warm up the catalytic converter so it will be warm when needed. Once the engine is up to temperature then it will turn off if not needed. It will run longer in cold weather in order to get up to temperature and to provided cabin heat depending on temperature setting.

Even when you first press the accelerator with the engine running, you first run on the electric motor, MG2, until up to about 15 mph and then the engine starts helping out. Once up to speed with the engine warm, when you let off the accelerator on level ground, the engine can cut off and you are then on batteries and electric motors until the engine needs to come back on for power requirements.

You need to search on here for how the Prius works and get a better understanding.

 

If the battery is low, the ice will start as soon as you power on to start recharging!

 

Sounds normal to me. This post is in the wrong area and should be moved to the Gen II area.

You might want to read http://priuschat.com/forums/knowled...12919-five-stages-prius-hybrid-operation.html and the first PDF of http://priuschat.com/forums/gen-ii-...angauge-best-threads-mileage-improvement.html.

 

It seems counter-intuitive I know, but you want to get maximum use of the engine at efficient outputs.

All the energy in the battery has ultimately come from fuel. If it got there by braking, you had to use more energy to accelerate to the speed you braked from. If it got there by braking downhill, you had to use more energy to get to the top of that hill. Both charging and discharging the battery are lossy processes. It's better to use engine power now than to drain the battery and recharge it later.

(Incidentally, most of the energy in the battery got there through running the engine slightly harder than was necessary for cruising - though this may not have consumed much more fuel as the engine's efficiency improves from 1,000 to about 3,500rpm, and drops after that.)

Generally you should aim to accelerate using moderate engine power - often called 'brisk' acceleration here. That is, use the engine, with more revs than you would to cruise, but not too hard. One rule of thumb is to keep instant fuel economy (iMPG) about half your speed (for US owners: British owners about 60% of speed as a UK gallon is 20% larger than a US gallon). You can see iMPG numerically by switching to the 'Energy' display on the screen, which shows the battery level and arrows indicating whether energy is flowing from the engine, to the motor and to or from the battery.

Another approach, using the same screen, is to try to accelerate while keeping no net flow to or from the battery - showing only pink arrows from engine to wheels and motor and yellow arrows from motor to wheels, but no yellow arrow from or green arrow to the battery. For the most part this leads to about the suggested iMPG anyway.

On my car, also a 2008, the engine automatically starts 12 seconds after going READY unless you've pressed the EV switch (factory-fitted in Europe) to stop it. However, it's best to only do this if you're planning to move the car a short distance and immediately switch off. The EV switch is otherwise mostly useless, except for keeping the engine off in Stage 3a if you're going to be travelling below 34mph for a long period and can't stop to get into Stage 4.