Catalytic Converter Warm Up In Park, Why?

[Angel And The Wolf]

I own a 2011 Prius Hybrid. When I turn the car on in the morning, after a few seconds, the ICE starts and runs for a minute or so, to bring the catalytic converter up to operating temperature.

I understand why the converter needs to be within a certain temperature range to do it's job, but my ICE doesn't need to run while sitting in the driveway, in park, going nowhere.

Doesn't the cold catalytic converter pollute just as much regardless of where and when it does it's warm up, and can't the warm up be done during the time I actually NEED the ICE assist, and NOT before I put the car in Drive or Reverse?

Has anyone defeated this useless "Warm Up in Park" protocol?

[Daox]

Originally Posted by Angel And The Wolf

Has anyone defeated this useless "Warm Up in Park" protocol?

Yep. I don't turn my car on before I am ready to drive it. This is driving tip #61 in our hypermiling tips list. If you want to listen to the radio or whatever, just push the start button once or twice without holding the brake pedal down.

61) Start up: wait for the opportunity to move
Don't start the engine until there's actually an opportunity to start driving: eg. a gap in traffic when exiting a driveway or parking space.

You can plan even further ahead: don't turn the key until you know you can time the next traffic light down the street.

[Angel And The Wolf]

Yes, those are all good suggestions, but could the ICE Start signal be interrupted somehow when the transmission joy stick is in Park?I know the stick itself has no real "position" other than to momentarily activate a D, R, N, or B push buttons, but can the Drive activation signal be "felt" and used to complete the signal wire that activates the ICE when needed?

Maybe the "Throttle Position Sensor" could be used to "authorize" the ICE activation circuit? Of course, the low battery ICE activation needs to be unaltered.

[Angel And The Wolf]

Originally Posted by Daox

You can plan even further ahead: don't turn the key until you know you can time the next traffic light down the street.

It would be a dream if my little town (Abilene, Texas) would use computers to time it's traffic lights with each other. I never make it through two lights in a row on green, but I've seen this work in Wichita Falls on the main highway through town. You stop at the first one, then, if you maintain 30 MPH, every light turns green just before you get to it.

Saves gas, and idling pollution.
Jack rabbit acceleration just gets you to the next light on red.

[Daox]

I'm not sure about the 3rd gen, but pressing the EV button (which is a mod) on the 2nd gen before the engine starts up does put the car in EV mode and stops the engine from starting initially (unless heat, low battery, higher power demand from the gas pedal, etc).

[redpoint5]

Originally Posted by Angel And The Wolf

I own a 2011 Prius Hybrid. When I turn the car on in the morning, after a few seconds, the ICE starts and runs for a minute or so, to bring the catalytic converter up to operating temperature.

If your climate control settings are turned off, the engine should not start up immediately.

I always park with the climate control off so that it doesn't turn the engine on the next time I start.

[Angel And The Wolf]

Thanks. I have also noticed that if I'm sitting in the parking lot listening to my radio, if the electric assist steering wheel is cocked one way or the other, it drains on the battery, and the ICE runs to keep the battery charged. Straightening the wheel often turns off the ICE.

[Stubby79]

I'd assume because it will warm up faster if there is no air flow from moving to cool it off. (Though I agree, it's silly)