DesertDog — Thanks for setting me straight. I stand corrected about the operation of the FEH. The TCH is definitely different. It appears that, from cold start-up, provided that one accelerates moderately, initially the power comes mainly from the battery, with the ICE providing a smaller fraction. Then, within the first half minute or so, the power fraction smoothly changes over, so that most of the power now comes from the ICE, and less (eventually zero) from the battery. The FEH's behavior sounds more like what I've read about the Prius' operating strategy.

Stan

 

What Gary and Carl says works well in above freezing weather.

I'm finding there are different sets of rules based on outside air temps.

In very cold weather ( 10's above and below zero ) I'm not seeing any advantage to this strategy, and am leaning towards this being a dis-advantage.

It is helpful to do this in warm weather though, for sure.
-John

 

So, is it better to accelerate more aggressively to get things to warm up quicker when it's that cold?

I try to accelerate slowly starting up from home in the morning, but it's not possible very often. I'm in a rural area and have to pull out onto a 2 lane highway (55mph speed limit) and have a slightly uphill grade to begin with. I try to accelerate slowly until I get to the top if the hill, and gain speed on the downhill side, but traffic does not always allow this. There's a hill from the other direction too, and many times someone comes over the hill behind me right after I pull out.

-- Rick

 

I think Ford developed this warm-up strategy because of cold weather. In freezing weather, you can bet I'd invest in a block heater and a good radiator block also.

It may take more time to heat things up, so yes, I may change how I would deal with the Ford strategy. More than likely I would only EV enough before parking to allow the needed SoC to complete the warm-up strategy. Regen using "L" will not be much help during warm-up, but I would want the battery as low as possible (~32%) after the warm-strategy was complete. The generator (MG1) would put the load on the engine and heat both the HV battery while charging at the same time. This would also be a good time to pulse and glide ICE-ON in neutral. I would test for EV mode in neutral with the brake tap when the SoC reaches ~42%.

In addition, I would look into reducing cold air flow not only through the radiator, but the intake and engine compartment also. It just seems to me every challenge I've had to increase my MPG, I've overcome or reduced the hit. The FEH gives me more options to deal with conditions than I've ever seen in a vehicle. The heater core bypass helped so much this past summer running the A/C, and I can reconnect it in a few minutes to the stock installation.

GaryG