ICE Repeadedly Starts With HVB Full

[jchunter]

With colder weather, my ability to hypermile short trips has become more difficult because the ICE starts way too often even though the HVB is full and the car is moving on level road.  My average mpg is dropping rapidly.  I used to do short trips in warm weather on a full battery without starting the ICE.

 

 Is there is a control or mode in the C-Max that will discourage the ICE from starting with a full HVB?

Edited December 19, 2015 by jchunter

[scottwood2]

The heater, or should I say limiting the use of the heater will help.   Yes cold weather drops the FE.   The electric seat heaters help.  I can use these until the car gets warmed up some.  Then I turn on the cabin heater.  Short trips make it harder to get MPG up.  

 

A search will find lots of information on this topic.   Try this link as a starting point.   

 

http://fordcmaxhybridforum.com/topic/3183-suggested-tips-for-cold-weather-driving/?hl=%2Bcold+%2Bweather+%2Btips

[homestead]

You can turn the heater temperature down or off until the car is up to temperature.

I use the seat heaters until the car is warmed up.

Other time I just turn the heater temp down until it goes into EV.

[ptjones]

Here is a shorter thread: http://fordcmaxhybridforum.com/topic/5511-how-to-improve-winter-mpgs/   It talks about Oil Pan and ICE Block Heaters  and Grill Covers that will make a big difference on short trips. :)

 

Paul

[markd]

Even in the summer I have found that short trips aren't conducive to good fuel economy. The winter hurts the mpgs, last year I got down to 32.2 mpg lifetime, now I'm at 41.2, just like in baseball it's all about averages.The way things went last summer I expect 45 mpg by next fall.

[hybridbear]

With colder weather, my ability to hypermile short trips has become more difficult because the ICE starts way too often even though the HVB is full and the car is moving on level road.

This is likely because you have the HVAC turned on. Turning on the heater will force the ICE to run more to provide cabin heat. When the HVAC system is requesting heat, the car keeps the coolant temp above 100 C. This is not easy to do in the winter since the ICE turns off so much. The higher you set the HVAC temp, the more the ICE must run. Grille blocking with foam pipe insulation helps. Leaving the HVAC on when shutting down the car may cause the ICE to start as soon as you turn on the car as well. Turning off the HVAC before turning off the car can help with that.

[jchunter]

Thanks for all the suggestions.  I get it.  All I need to do is put up with a cold butt and frigid interior.  ;) 

 

So I ran an experiment:  I turned the heater temp down to ambient (60 deg), dropped the fan to lowest and drove gently out of the garage down a level road with nearly full battery,.  Regardless, after a few moments the ICE started.  So I accelerated to 30, took my foot off the gas but the ICE refused to shut down....  So it seems I need more than a cold butt to get this thing to behave.  

 

HybridBear, I thought the C-Max had a heat pump that ran off the HVB.  If so, it should work without any heat in the ICE radiator.  What is the scoop here??? 

[ptjones]

Thanks for all the suggestions.  I get it.  All I need to do is put up with a cold butt and frigid interior.  ;)

 

So I ran an experiment:  I turned the heater temp down to ambient (60 deg), dropped the fan to lowest and drove gently out of the garage down a level road with nearly full battery,.  Regardless, after a few moments the ICE started.  So I accelerated to 30, took my foot off the gas but the ICE refused to shut down....  So it seems I need more than a cold butt to get this thing to behave.  

 

HybridBear, I thought the C-Max had a heat pump that ran off the HVB.  If so, it should work without any heat in the ICE radiator.  What is the scoop here??? 

It's not cold in Phoenix, LOL. Don't you have seat warmers?  Is your CMAX an energy? Hybrids don't have electric heaters.  The ICE shouldn't be coming on if you don't have the HVAC on. ;)

 

Paul

[homestead]

Thanks for all the suggestions.  I get it.  All I need to do is put up with a cold butt and frigid interior.  ;)

 

So I ran an experiment:  I turned the heater temp down to ambient (60 deg), dropped the fan to lowest and drove gently out of the garage down a level road with nearly full battery,.  Regardless, after a few moments the ICE started.  So I accelerated to 30, took my foot off the gas but the ICE refused to shut down....  So it seems I need more than a cold butt to get this thing to behave.  

 

HybridBear, I thought the C-Max had a heat pump that ran off the HVB.  If so, it should work without any heat in the ICE radiator.  What is the scoop here??? 

It is normally difficult to go into EV in the first mile or so once you pass 35 mph.  After a mile or two it should go into EV.

[Bill-N]

It's my understanding that the lithium-ion battery also likes/needs to be warmed up.

[jestevens]

It works relatively like the prius, so typically within the first seven seconds of being in "Ready" mode the ICE is probably going to start to "prove" the engine and warm up the catalytic converter. It needs to prove the engine can start, otherwise you'd eventually run out of HVB and not be able to charge..Catalytic converter has to be hot enough to handle emissions.

 

The car probably has PTC electric heater but if there is more than a few degrees difference it will start the ICE to generate lots of heat. If you have the touch screen you can touch the little leaf looking icon near the bottom center to see where the energy is being used.

 

The car works optimally after about a 20 minute drive..

 

Someone mentioned about the HVB ambient temperature - I have heard a good rule of thumb is that if you are uncomfortable in the passenger compartment because it is too hot or cold then the HVB will also be "uncomfortable" too - as in potentially shorten its life.

 

I think one thing C-MAX doesn't have that the Prius has is a thermally insulated coolant storage tank - Toyota stores some warm coolant in here and use electromechanically actuated valves to isolate or add the coolant to engine .. it helps shorten engine warm up time in the prius for as long as the coolant in the tank can stay warm (about 2 hours).

 

Even in the wintertime, if I'm getting 34MPG that was much better than my HHR's 22-25MPG

[ptjones]

Thanks for all the suggestions.  I get it.  All I need to do is put up with a cold butt and frigid interior.  ;)

 

So I ran an experiment:  I turned the heater temp down to ambient (60 deg), dropped the fan to lowest and drove gently out of the garage down a level road with nearly full battery,.  Regardless, after a few moments the ICE started.  So I accelerated to 30, took my foot off the gas but the ICE refused to shut down....  So it seems I need more than a cold butt to get this thing to behave.  

 

HybridBear, I thought the C-Max had a heat pump that ran off the HVB.  If so, it should work without any heat in the ICE radiator.  What is the scoop here??? 

If you have the heater on at all the ICE is going to come on. ;) Try starting with no Heater, you should be able to stay in EV until you hit 35mph or run out of HVB.  Turn on EV+ and try to run down your HVB by the time you get home. :)

 

Paul

[scottwood2]

I try to start out with no hvac.   Then try to gently use the throttle to keep it in electric mode and run the battery down.   Then ICE will start and I try to keep my acceleration down (keep RPM about 2K).  This give ICE some time to warm up and slowly charge the battery back up.  This takes about a mile.  Then I try to run the battery out again and back to ICE.  A few cycles of this and my temp starts to move into the normal range.   On the 3rd time of doing this I then turn on the heat. 

 

This is what I do at 5:30 am.  Other times of the day is harder to do.  You learn tricks as you go and learn what the car wants to do in the warm up cycle.  

[jchunter]

It's my understanding that the lithium-ion battery also likes/needs to be warmed up.

Ah yes. That is the thing I couldn't control from the cockpit in my experiment. So even a cold butt may not solve my problem. Does anyone know how much energy the battery heater needs?

 

Still, the question remains as to whether the C-max hybrid gets whatever heat it needs from a heat pump compressor or from resistive electric heaters or from the ICE thunder banger.

[jestevens]

If it is like the Prius it uses the ICE as the main heat source and PTC heaters for supplemental electric heat.  I saw some references to PTC heater parts when I did a google search.  I don't know about the energi, that might have a different setup.

 

http://www.processtechnology.com/pdf/SmartOnearticle.pdf

 

The Prius also had independently controlled HVAC vents for interior vs. exterior air and the different heat sources that seemed more sophisticated than your typical gasoline car, I don't know if C-MAX has that setup but it would make sense if it did to try to improve warm-up times.

[stevedebi]

Ah yes. That is the thing I couldn't control from the cockpit in my experiment. So even a cold butt may not solve my problem. Does anyone know how much energy the battery heater needs?

 

Still, the question remains as to whether the C-max hybrid gets whatever heat it needs from a heat pump compressor or from resistive electric heaters or from the ICE thunder banger.

The hybrid uses engine heat. Only the Energi has dual systems, one electric for EV mode and one ICE based for hybrid mode. FWIW, the A/C is all electric.

 

BTW, I'm not sure setting the temp to 60 is ambient. Doesn't the hybrid have a "LO" setting for the HVAC? I have an Energi, so I'm not sure if the programming is the same.

[jestevens]

I saw that the "emergency response directions" specifically mention the PTC as a part of what is wired into the high voltage wiring in the Energi but no such mention for the hybrid so that makes sense.

[ptjones]

The hybrid uses engine heat. Only the Energi has dual systems, one electric for EV mode and one ICE based for hybrid mode. FWIW, the A/C is all electric.

 

BTW, I'm not sure setting the temp to 60 is ambient. Doesn't the hybrid have a "LO" setting for the HVAC? I have an Energi, so I'm not sure if the programming is the same.

If  the heat is turned on at all the ICE will come on, That's just the way it works until the ICE WT heats up. :)

 

Paul

Edited December 22, 2015 by ptjones

[SnowStorm]

BTW, if the HVAC is on when you start the car and you wanted it off, I think you have 5 seconds or so to turn it off before the ICE starts.

[jchunter]

If the heat is turned on at all the ICE will come on, That's just the way it works until the ICE WT heats up. :)

 

Paul

. This seems to be the case. Yesterday I had a chance to experiment with a complete HVAC shut down rather than just turning down the thermostat. What a game changer! For the first time ever, I was able to start up, drive down the street, and accelerate away from traffic light stops (gently) without ICE. I also was able to make much better use of regen charging at lights to sustain battery charge longer.

 

Now, all I have to do is convince my wife she is mistaken about the car being frigid.

Edited December 23, 2015 by jchunter

[hybridbear]

HybridBear, I thought the C-Max had a heat pump that ran off the HVB.  If so, it should work without any heat in the ICE radiator.  What is the scoop here??? 

Hybrid - ICE heat only

Energi - ICE heat or electric heater, no heat pump

 

It works relatively like the prius, so typically within the first seven seconds of being in "Ready" mode the ICE is probably going to start to "prove" the engine and warm up the catalytic converter. It needs to prove the engine can start, otherwise you'd eventually run out of HVB and not be able to charge..Catalytic converter has to be hot enough to handle emissions.

The Ford hybrids will not automatically start the ICE like the Prius. Check out the warm up stages thread for more info.

 

Ah yes. That is the thing I couldn't control from the cockpit in my experiment. So even a cold butt may not solve my problem. Does anyone know how much energy the battery heater needs?

 

Still, the question remains as to whether the C-max hybrid gets whatever heat it needs from a heat pump compressor or from resistive electric heaters or from the ICE thunder banger.

The battery is heated or cooled with fans that use cabin air. It isn't super effective. The HVB heats up the most by charging & discharging it by driving the car.

[raadsel]

 

The battery is heated or cooled with fans that use cabin air. It isn't super effective. The HVB heats up the most by charging & discharging it by driving the car.

 

A minor correction, the HVB is heated/cooled on the Hybrid by cabin air. The Energi can be heated/cooled by outside air, since charging frequently takes place with the car off and sunlight can make the cabin temperature much hotter than the outside temperature.

[hybridbear]

A minor correction, the HVB is heated/cooled on the Hybrid by cabin air. The Energi can be heated/cooled by outside air, since charging frequently takes place with the car off and sunlight can make the cabin temperature much hotter than the outside temperature.

The Energi also only appears to use outside air when charging, never while driving. Since this is the hybrid forum I didn't bother adding the Energi info. Thanks for sharing it for Energi owners that may read this thread.