Bought some inexpensive pipe insulation (foam) from hardware store to seal the front grille and I now have good heating and MPG. Going to work from NYC --> Upstate NY (more uphill) getting 43.8 and return trip: 46MPG (more downhill) traveling 57 miles each way w/heat on and low to mid 20F air temp.
I also let the car run more in ICE in the beginning to get the engine temp. up for more efficient fuel burning throughout the trip.
Edited by cmax-nynj, 10 February 2014 - 09:19 PM.