Warm-up, 2001-03 Prius, North America

These driving techniques can reduce but not eliminate the warm-up fuel burn of the 2001-03 Prius, NHW11. Unique to North America, the 2001-03 Prius has a hydrocarbon (HC) emission system that requires a 70C coolant temperature before fuel efficient, hybrid operation can begin.

IMPACT OF THESE DRIVING TECHNIQUES

These techniques bring my morning commute MPG from 51-53 MPG to 56-58 MPG. However, they are somewhat involved and distracting. Mastery takes practice in controlled environments, not when in a rush to get somewhere. Drivers who are used to manual transmissions seem to handle this technique best. Take your time to master the technique by working on just one part at a time. It needs to be easy, not some distracting menu taped to the visor (or windshield!)

A better solution is to use an engine block heater or thermistor hack to shorten the warm-up time to 17 miles per hour "N" mode. But when I forget to plug-in the heater or don't run with the thermistor hack, these backup driving techniques help.

These techniques have not been tested with the 2004-current and non-North American Prius so we don't know if they are effective in the other models. However, the other models have the advantage of allowing auto-shutdown at lower coolant temperatures (estimated to be 40-50C.)

Comments? Questions?

Bob Wilson