Hi All:
First off, thanks to everyone who provided me with some much-needed input on my new purchase. I notice that everytime I turn the heat on in the car, the engine starts right up. It will run in EV mode for a few minutes but eventually the motor starts even with a solid battery charge. This happens a lot even once the blue temperature light goes off. Is this normal? I'm in NY where the avg. temp is hovering around 36 degrees now. It almost seems as if the heater requires a lot of energy to stay powered. Should I expect similar results in the summer with the AC?

 

I've noticed since the cold weather has set in that the car doesn't go into EV mode until long after the blue temp light goes out - maybe 15 min or even more. Once the car has been operating for 30+ min or more and the passenger compartment has come up the temperature the car will go into and stay in EV mode very similar to the summer. Of course once the temperature gets down to single digits I would expect very little time in the EV mode.

 

With only a week under my belt with my NAH, I noticed the same thing and the temps here in PA in the Snow Belt have been in the upper 20's to low 30's.

Even so, I am still seeing about 34 MPG on the dash on the first tank with mostly city driving.

 

This is the unfortunate impact of cold weather on a hybrid vehicle. The first priority of the car is to keep the engine up to temp so that it can run efficiently, which is why it starts out running. Its second priority is to give you heat. Since it would be impractical to us the battery to generate heat, the source is the engine. That means the engine has to start up and burn some gas to generate heat to keep both you and itself happy. This puts fuel economy in third place.

The explanation for the engine running after the engine is up to temp is the state of the battery. NiMH batteries don't like to give or take a charge when they are below about freezing, so the system won't use it. Instead it keeps the engine running to drive the vehicle while it allows small currents to pass through the battery, which gets it warm along with cabin heat. This helps to give the battery a long life.