FEHL warm up stratagy question
#1
11-24-2008, 08:34 AM
Join Date: Jun 2008
Location: New Jersey. Land of high auto insurance and pollution.
Posts: 127
FEHL warm up stratagy question
I'd like to know if I understand the FEH's warmup stratagy correctly...
After starting a cold soak engine the Pcm will run the motor extremely rich until the coolant temp and catalytic converter rise to operating temperature.
If the above is correct, at what temp does the cat need to be for the engine to end the rich burn warm up stratagy?
After starting a cold soak engine the Pcm will run the motor extremely rich until the coolant temp and catalytic converter rise to operating temperature.
If the above is correct, at what temp does the cat need to be for the engine to end the rich burn warm up stratagy?
#2
11-24-2008, 04:14 PM
Re: FEHL warm up stratagy question
I'd like to know if I understand the FEH's warmup stratagy correctly...
After starting a cold soak engine the Pcm will run the motor extremely rich until the coolant temp and catalytic converter rise to operating temperature.
If the above is correct, at what temp does the cat need to be for the engine to end the rich burn warm up stratagy?
After starting a cold soak engine the Pcm will run the motor extremely rich until the coolant temp and catalytic converter rise to operating temperature.
If the above is correct, at what temp does the cat need to be for the engine to end the rich burn warm up stratagy?
For the best FE, you want the least amounts of warm-up strategies as possible during a day. I take it real easy on the electric motors to reserve as much SoC as possible while the engine timimg is being retarded for heating the CAT.
GaryG
#3
11-24-2008, 05:17 PM
Re: FEHL warm up stratagy question
From a cold start but with an engine block heater, I have gone into EV within 1 mile in 28 degree weather. It doesn't take the CAT very long to heat up. The radiator coolant temp (FwT on the Scanguage II) needs to exceed 154 and the engine heat temp (CHT on Scangugae II) needs to exceed 188. Both Fwt and CHT take longer to reach operating temperature than the CAT in winter temperatures.
#4
11-25-2008, 06:13 AM
Join Date: Jun 2008
Location: New Jersey. Land of high auto insurance and pollution.
Posts: 127
Re: FEHL warm up stratagy question
Would wrapping the exhaust header, downpipe and cat shorten the time to "light off" after initial cold soak start and lengthen the time unitl the ICE needs to kick back on in stop and go rush hour trafic? Or woould wrapping the cat just overheat it and lead to its early demise?
#5
11-25-2008, 07:34 AM
Re: FEHL warm up stratagy question
Would wrapping the exhaust header, downpipe and cat shorten the time to "light off" after initial cold soak start and lengthen the time unitl the ICE needs to kick back on in stop and go rush hour trafic? Or woould wrapping the cat just overheat it and lead to its early demise?
GaryG
#6
11-25-2008, 08:25 AM
Join Date: Jun 2008
Location: New Jersey. Land of high auto insurance and pollution.
Posts: 127
Re: FEHL warm up stratagy question
My main reason for trying to shorten the cold soak warm up stratagy is obviously better FE. Seems the only practical mechanical method would be a block heater. Now I just need to convince my townhome assoc. to let me run some underground electrical to our parking space. That should be fun. Maybe I'll do it and just forget to tell them.
The next logical step would be to change my wifes driving habits during the first mile or so. On her morning commute to work the first 0.8 miles is on a 25 MPH road that is 0.2 miles flat, 0.5 miles slight decline, then 0.1 slight uphill to a traffic light where she turns onto a local highway (US 1). From there it is 4 miles of 45 - 50 MPH stop and go traffic with traffic lights until she turns off onto a 40 MPH road for the last mile to work. Shes doing great on that last mile, setting the cruise control to 38 MPH and going almost the entire way in EV. Any ideas for increasing the first 0.8 miles?
#7
11-25-2008, 09:18 AM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: FEHL warm up stratagy question
I would bet that the best result, FE wise, for the money invested would be to use a small electric heater plugged into a house outlet and on a timer to pre-heat the passenger cabin.
I would not "mess" with any sort of engine block heater unless the vehicle will otherwise get inordinately COLD (Cut Bank MT in the wintertime), as that might result in premature failure of the catalyst.
I would not "mess" with any sort of engine block heater unless the vehicle will otherwise get inordinately COLD (Cut Bank MT in the wintertime), as that might result in premature failure of the catalyst.
#8
11-25-2008, 11:10 AM
Re: FEHL warm up stratagy question
Ok, so unless I want to roast some marshmellows over a $35K bonfire I'll rule out insulating the cat.
My main reason for trying to shorten the cold soak warm up stratagy is obviously better FE. Seems the only practical mechanical method would be a block heater. Now I just need to convince my townhome assoc. to let me run some underground electrical to our parking space. That should be fun. Maybe I'll do it and just forget to tell them.
The next logical step would be to change my wifes driving habits during the first mile or so. On her morning commute to work the first 0.8 miles is on a 25 MPH road that is 0.2 miles flat, 0.5 miles slight decline, then 0.1 slight uphill to a traffic light where she turns onto a local highway (US 1). From there it is 4 miles of 45 - 50 MPH stop and go traffic with traffic lights until she turns off onto a 40 MPH road for the last mile to work. Shes doing great on that last mile, setting the cruise control to 38 MPH and going almost the entire way in EV. Any ideas for increasing the first 0.8 miles?
My main reason for trying to shorten the cold soak warm up stratagy is obviously better FE. Seems the only practical mechanical method would be a block heater. Now I just need to convince my townhome assoc. to let me run some underground electrical to our parking space. That should be fun. Maybe I'll do it and just forget to tell them.
The next logical step would be to change my wifes driving habits during the first mile or so. On her morning commute to work the first 0.8 miles is on a 25 MPH road that is 0.2 miles flat, 0.5 miles slight decline, then 0.1 slight uphill to a traffic light where she turns onto a local highway (US 1). From there it is 4 miles of 45 - 50 MPH stop and go traffic with traffic lights until she turns off onto a 40 MPH road for the last mile to work. Shes doing great on that last mile, setting the cruise control to 38 MPH and going almost the entire way in EV. Any ideas for increasing the first 0.8 miles?
The engine block heater on a timer set 3 hours prior to start-up is what I'm hearing from Debbie Katz. She uses the block heater year round in WI in her '05 FEH and says it really reduces the time to go EV. My '09 here in Florida heats up so quickly with the recommendations above, I usually have to wait for my SoC to get above 42% to go EV. Therefore there is no reason for me to install a block heater.
One last thing you may want to consider is dressing warm and wait till the coolant temperature get real hot before running the cabin heater. The cabin heater will delay engine warm-up and will shorten your EV time. If your climate control is set to anything but OFF, the electric heater pump will circulate coolant in the heater core while in EV. Remember, when the engine shutsdown, the belt driven coolant pump stops also. Ford had to add the electric coolant pump for EV only to keep the cabin warm.
GaryG
#9
11-25-2008, 12:32 PM
Ridiculously Active Enthusiast
Join Date: Sep 2006
Location: Beautiful Pacific NW
Posts: 1,678
Re: FEHL warm up stratagy question
I find the best way to heat-up the battery is to drain it as much as possible the night before shutting the engine off.
Assuming that happens "naturally" then all well and good. But if you are somehow artifically draining the hybrid battery that seems self-defeating to me.
The warm-up strategy will take the SoC below the normal operating limit of 40% the next morning. You may not get any regen in cold weather but your small generator (MG1) will be working overtime right after the warm-up strategy to recharge the battery. This heavy charging is the only way I know to heat the battery cells the quickest. In addition, engine load turning MG1 will help further heat the engine and CAT. No matter what, the best FE is a slow acceleration and avoid any hard acceleration that will disrupt the warm-up strategy of retarding the timing. On the '09 the cold engine idle is still 1,600 RPM so avoid any acceleration that will increase that idle. The warm engine idle during the warm-up strategy will be around 1,100 RPM, so avoid breaking that idle till the strategy is finished.
The engine block heater on a timer set 3 hours prior to start-up is what I'm hearing from Debbie Katz.
What effect will a preheated engine have on the catalyst warm-up cycle...? Adverse..??
Engine "arrives" at the selected heat level (long) before the Catalyst temperature has been raised to operational temperature, thereby foreshortening the catalyst warm-up cycle. Resulting in the catalyst failing prematurely, 70,000 miles instead of 150,000...??
She uses the block heater year round in WI in her '05 FEH and says it really reduces the time to go EV. My '09 here in Florida heats up so quickly with the recommendations above, I usually have to wait for my SoC to get above 42% to go EV. Therefore there is no reason for me to install a block heater.
One last thing you may want to consider is dressing warm and wait till the coolant temperature get real hot before running the cabin heater. The cabin heater will delay engine warm-up and will shorten your EV time. If your climate control is set to anything but OFF, the electric heater pump will circulate coolant in the heater core while in EV. Remember, when the engine shutsdown, the belt driven coolant pump stops also. Ford had to add the electric coolant pump for EV only to keep the cabin warm.
GaryG
Assuming that happens "naturally" then all well and good. But if you are somehow artifically draining the hybrid battery that seems self-defeating to me.
The warm-up strategy will take the SoC below the normal operating limit of 40% the next morning. You may not get any regen in cold weather but your small generator (MG1) will be working overtime right after the warm-up strategy to recharge the battery. This heavy charging is the only way I know to heat the battery cells the quickest. In addition, engine load turning MG1 will help further heat the engine and CAT. No matter what, the best FE is a slow acceleration and avoid any hard acceleration that will disrupt the warm-up strategy of retarding the timing. On the '09 the cold engine idle is still 1,600 RPM so avoid any acceleration that will increase that idle. The warm engine idle during the warm-up strategy will be around 1,100 RPM, so avoid breaking that idle till the strategy is finished.
The engine block heater on a timer set 3 hours prior to start-up is what I'm hearing from Debbie Katz.
What effect will a preheated engine have on the catalyst warm-up cycle...? Adverse..??
Engine "arrives" at the selected heat level (long) before the Catalyst temperature has been raised to operational temperature, thereby foreshortening the catalyst warm-up cycle. Resulting in the catalyst failing prematurely, 70,000 miles instead of 150,000...??
She uses the block heater year round in WI in her '05 FEH and says it really reduces the time to go EV. My '09 here in Florida heats up so quickly with the recommendations above, I usually have to wait for my SoC to get above 42% to go EV. Therefore there is no reason for me to install a block heater.
One last thing you may want to consider is dressing warm and wait till the coolant temperature get real hot before running the cabin heater. The cabin heater will delay engine warm-up and will shorten your EV time. If your climate control is set to anything but OFF, the electric heater pump will circulate coolant in the heater core while in EV. Remember, when the engine shutsdown, the belt driven coolant pump stops also. Ford had to add the electric coolant pump for EV only to keep the cabin warm.
GaryG
Does the FEH even have an engine driven water pump..??
#10
11-25-2008, 06:11 PM
Re: FEHL warm up stratagy question
Willard, a space heater is dangerous inside a car, so don't even consider that. Do your children know where you are?
GaryG
