Road Trip Observations with Torque Pro

[hybridbear]

During our road trip I've been able to gather and analyze a lot of data about how the car works. I'll try to break it down in parts.

[hybridbear]

First topic: grille blocking

 

We've had the grille blocked for the whole trip. When we left MN the temps were around -5 F and th coolant temp only reached 180-185 maximum. The transmission fluid temp only could reach 115 at 0 F ambient temp. The motor and generator temp sensors peaked around 130 at 0 F. The maximum temp increase for those components has thus far increased linearly as the ambient temp has risen. Thus at 40 F ambient the transmission fluid reached 145-150 F. The motor coil (typically the hottest hybrid component under the hood) reached 170-175.

 

As the ambient temp rose from -5 to 0 to 40-45 the peak ICE coolant temp went up to 215-220. Some of this rise is likely due to the fact that as the ambient temp rose we were using less cabin heat and eventually none so we weren't cooling the engine down to heat the cabin.

 

It's worth noting that even climbing the mountains did not cause the ICE coolant temp to exceed 220 F even with full grile blocking. Also, the ICE cooling fan never came on. The transmission and hybrid components did not increase any higher than their previously posted maximums even while climbing.

 

Later today we'll be descending down from the mountains to the desert where the temps are in the 70s and I'll post more about temps once we are in the warm weather.

 

The HVB fans cool not only the HVB but also the DCDC converter. The HVB fans would kick on anytime the DCDC converter reached 176 F. The fans would run until its temp dropped to 165 F. This drop would take less than a minute. Once the DCDC converter temp dropped to 165 the fan would turn off. It would take about 5 minutes or less for the DCDC temp to climb back to 176 and make the fan come on again. When the HVB fans are running for hours to cool the HVB the DCDC converter temp drops to only a few degrees warmer than the temp of the air being blown across it. The HVB inlet often showed a temp of around 68-70 F and the DCDC converter temp would drop to around 80 F.

[hybridbear]

Second topic: eCVT behavior

 

Elsewhere the different modes have been defined. You can review the topic in this section about the power flow meter for descriptions of some of the modes I'm going to reference.

 

When driving at freeway speeds the car likes to show "hybrid drive" on the power flow screen. Typically what happens is that the ICE turns gasoline into mechanical energy, the generator motor then applies negative torque to slow down the ICE and control the planetary gear set. It consumes electrical energy to do this. The traction motor then siphons off some of that mechanical energy and it converter it to electrical energy to power the generator. Typcailly the car does very little charging of the HVB in this scenario. The traction motor seems to try to siphon off only as much mechanical energy as it needs to power the generator and the DCDC converter for all the electrical systems of the car.

 

Edit: the above paragraph and the one sentence one below describe negative split mode as posted by GrySql here: http://fordfusionhybridforum.com/topic/9602-ffh-factoids-parts-quiz/?p=90956

 

When the car does want to charge the battery the traction motor just siphons off more mechanical energy and the excess (not used by generator or DCDC converter) is stored in the HVB.

 

Edit: the two paragraphs below describe variations in positive split mode as posted by GrySql at the aforementioned link.

 

At lower speeds the roles of the generator and traction motor are reversed. In city driving for example, the ICE's mechanical energy output is almost largely (10+ kW) consumed by the generator which then sends electricity to the traction motor which sends power to the wheels. Any excess is stored in the HVB. This activity also is labeled "hybrid drive" on the power flow screen.

 

Sometimes the car shows "charging HV battery" on the screen. This means that both the generator and the traction motor are consuming mechanical power from the ICE and turning it into electrical energy. This mode is uncommon at highway speeds but it will happen when the HVB charge is low. This mode is more common in city driving. In this mode the only source of power going to the wheels is the ICE.

Edited January 11, 2015 by hybridbear

[mwr]

First topic: grille blocking

 

We've had the grille blocked for the whole trip.

Is grill blocking something "external" that you do to your FFH?

[GrySql]

Is grill blocking something "external" that you do to your FFH?

This Thread discusses 'Grill Blocking' in all it's forms and the reasons and results of doing it.

http://fordfusionhybridforum.com/topic/7788-preparing-for-winter-with-a-comprehensive-strategy-to-improve-mpgs-including-grille-blocking-more/?p=68748

[lolder]

In SW FL with my 2010, I never see ICE coolant over about 200 F. I would have taken the blocker off going up the mountains.

[hybridbear]

In SW FL with my 2010, I never see ICE coolant over about 200 F. I would have taken the blocker off going up the mountains.

According to Ford the ideal operating temp for the ICE is 205-225. We did not exceed 225 and thus there was no issue. The 2010 likely operates differently.

[hybridbear]

Third topic: grille blocking in warmer weather

 

As we descended down out of the mountains the temps were in the 60s & 70s. The ICE coolant never went higher than 220 F and the ICE cooling fan never turned on. I did remove a couple rows of foam at one gas stop but it had no impact on temperatures that I could detect. For now the upper grille is completely blocked and the lower grille is partially blocked. I plan to leave it that way for now.

[hybridbear]

Fourth topic: descending steep grades

 

I was very curious to see how the Energi would behave differently from the hybrid when descending down out of the mountains. The maximum amount of regen you could recapture in the hybrid would be about 0.5 kWh. With the Energi you could potentially regen 5.0 kWh or more. During one descent of about 2000 feet of elevation we were able to put over 1.2 kWh of electricity back into the HVB. 1.2 kWh is about enough energy to drive 6-7 miles in the city or about 5 on the highway.

 

We drove a number of 6% grades (according to the signs) and never had engine braking kick in. We often saw that the car was charging the HVB at a rate of 20+ kW while going down the grades. We could hear the electric motor whirring during these periods. The HVB temp spiked about 10 degrees during one stretch of 6% grade for about 10 miles (the same stretch that put over 1.2 kWh back into the HVB). I tried to keep the car in EV Now when going up the small uphill stretches after the grades to keep the HVB charge low enough to accept more charge.

 

Once the HVB reached 80 F going down the aforementioned steep grade the HVB fans came on and stayed on until the temp dropped back to 72 F, this took more than an hour and lowered the DCDC converter temp down to about 85 F during this period. Once the HVB cooled to 72 F the HVB fans turned off and the DCDC converter temp rose back up to 176 F. The HVB fans only came on after that when the DCDC converter hit 176 F and they shut off when it dropped to 165 F as described above.

 

In the Energi we could also shift to Low for maximum regen. When driving at freeway speeds we could get 35 kW of regen by shifting to L. For the most part we had the Adaptive Cruise Control set at 65 MPH going down the hills. Sometimes there would be a sign about an upcoming curve saying 50 MPH. When I saw one of those signs I would cancel the ACC and shift to L. This would kick the regen up to 35 kW and slow us down. I don't think you can do this in the hybrid since shifting to L usually makes the ICE come on.

 

Temperatures did climb significantly while going downhill in the traction motor. The coil temperature climbed to over 190 F during those periods of extended charging. It was typically about 170 F when driving on the freeway with the ICE on. The inverter temp climbed to about 140 F, as opposed to 110-120 F when the ICE is doing most of the work. Once the ICE began doing the work again after we finished descending the temps dropped.

[hybridbear]

Fifth topic: Adaptive Cruise Control, Hill Assist & steep grades

 

I tried descending steep grades with only ACC and with ACC & Hill Assist. Both methods yielded the exact same results for regen & vehicle speed. When using ACC only the spinning regen circle would appear and the brake lights would illuminate. When using ACC & Hill Assist the regen circle did not appear and the brake lights did not illuminate. I mostly used the Hill Assist button, but in some situations where I wanted the brake lights to illuminate based on traffic around us I did not activate the hill assist button so that the brake lights would be on.

 

I used the cruise control to speed up slightly on the downhills where appropriate and it worked great. The ACC is very smooth at controlling vehicle speed during regen.

[hybridbear]

Sixth topic: ICE behavior

 

I also monitored some additional ICE operating parameters that I had not previously observed. While my wife was driving I had lots of time to observe the behavior of the car. I monitored the AF Ratio commanded & the actual AF ratio along with Spark Advance and VCT Advance.

 

VCT refers to Ford's version of VVT. I believe this is how Ford makes our ICE follow the Atkinson cycle. A negative VCT number (retarded timing) means that the intake valve is staying open for that many degrees of the rotation of the combustion stroke, allowing air back into the intake.

 

The AF Ratio was about 14.8 or 14.9 when at high elevations using 86 octane gas from gas stations at high altitudes. At lower altitudes the AF ration was bout 14.5 or 14.6. The car would go to a richer mixture when under heavy load (14.3 or 14.4 at low elevations and 14.5 or 14.6 at high elevations).

 

Another thing that was very interesting to observe was the spark advance. Under light load conditions (cruising at 65 MPH on flat terrain) the ICE only needs to produce about 20 kW to propel the car. The car is in negative split mode as described above. Typically the spark advance was about 30 degrees at this level of load. The RPM was usually around 1900-2000. The VCT advance was about -20 degrees.

 

Under higher load conditions (ascending a grade at 65 MPH) the ICE was producing 30-40 kW and was revving to 2500-2900 RPM. At the higher load conditions the spark advance decreased to only about 15-20 degrees. The VCT advance became more negative, more retarded, to about -35 degrees. This means that under a heavy load the car keeps the intake valve open longer to allow more air back into the intake manifold and the spark was advanced less, meaning that the ICE was waiting longer to fire the spark to burn the air & fuel mixture.

 

When the ICE would first shift from a light load to a heavy load the spark advance would momentarily drop to almost 0 (3-8 degrees usually) and the VCT advance would go all the way to -38 to -40 degrees. When the ICE would first start it would follow a similar pattern and then stabilize within 1-2 seconds.

 

I don't know a whole lot about how ICEs work so perhaps others who know more can further explain what's occurring here.

[lolder]

The VCT is varying to keep the ICE at optimum Atkinson cycle and the spark is changing to avoid knocking. The 1-2 second stabilization period is why it's important to have steady pedal pressure. Nice data.

[acdii]

You might have recovered more had you kept it out of grade assist and let the eCVT braking capture it all. I know of a couple Energi owners who recovered a full charge going down a long grade using ACC.

 

I will have to think about the timing, I have a theory on it, but trying to correlate it with a normal ICE is confusing me. For more power you advance the spark to just before detonation, but with the intake hanging open, that just creates a back fire. Seems like the goal is to reduce the amount of back force on the ICE by not compressing the A/F mixture. On startup that is exactly what it is doing, but while running, that part has me puzzled. The MG spins up ICE with no spark or fuel, once the ICE is at the proper RPM, then fuel and spark are started. The spark at or near TDC at that point is to produce the initial punch on the pistons,since the intakes are still open just before that point, then increase the advance to build power. I just dont understand the reasoning for it while in operation, unless its to keep RPM down in the power band. It might be based on Diesel fundamentals too since most diesels operate the most efficient between 1500 and 2300 RPM.

[hybridbear]

You might have recovered more had you kept it out of grade assist and let the eCVT braking capture it all. I know of a couple Energi owners who recovered a full charge going down a long grade using ACC.

 

I think we did get it all because we didn't use the brake pads at all. Those trips down the mountain had 100% brake scores. One trip showed over 5 miles of regen.

[corncobs]

Some cool observations HB thank you. I guess it makes the miles go by fast if you have a nice you like the Torque Pro. :)

[acdii]

I think we did get it all because we didn't use the brake pads at all. Those trips down the mountain had 100% brake scores. One trip showed over 5 miles of regen.

When you used the grade assist the ICE kicked on and regen stopped, so you lost some regen there. How much, unknown. Just something to keep in mind with the Energi.

[hybridbear]

When you used the grade assist the ICE kicked on and regen stopped, so you lost some regen there. How much, unknown. Just something to keep in mind with the Energi.

The ICE never came on. That's what my posts above say. With the hybrid the ICE would have come on, with the Energi it did not.

[GrySql]

So, the real question is:

Are you basking in the sun in Palm Desert, getting your CA tan lines yet?

[acdii]

The ICE never came on. That's what my posts above say. With the hybrid the ICE would have come on, with the Energi it did not.

oops missed that, but didn't you say the circles went away when you did? Sorry too lazy to reread

[hybridbear]

oops missed that, but didn't you say the circles went away when you did? Sorry too lazy to reread

Regen spinning circle appears when using ACC, but not when using Grade Assist. Regen spinning circle means brake lights are on. Both produce the same amount of regen to slow the car.

[ptjones]

hybridbear great job! From all the info that you accumulated can you come up with an explanation why we lose 2mpg for every 10*F drop in temps from 70*F?

 

I just made a trip to AZ and back and I experimented with controlling WT with heater and Lower Grill removal and reinstalling. To start with I had all three grills covered and then added clear packing tape to cover up all joints around head lights, hood and fog lamps. So the only air getting into engine compartment was from underneath and wheel wells. The thermostat starts to open around 180*F and is Fully open at 202*F. Normal operating temps are 202-212*F according to FORD Hotline Assistance Request and shutters open up at 215*F with update at FWY speeds confirmed by web cam.

 

Things I learned on this trip are I got maybe 1mpg better keeping WT in the 200*F-215*F over 220*F-230*F range (Smart Gauge WT starts to move off middle at 228*F) .

Second: Having the whole front end taped didn't change the 2mpg drop for every 10*F drop in temp. At 20*F I was getting 39.5mpg and 40*F/43.5mpg.

Third: tapping off top grill raised IT by +20*Fto+30*F vs open.

Forth: P&G is worth at least 2mpg over running ICE all the time with help from EV assist and the WT ran cooler at FWY speeds.

 

I was hoping by keeping ICE compartment warmer it would help the drop of mpg's with outside temp drop. It probably helps overall mpg's, but not the periodic 2mpg drop. :)

 

Paul

Edited January 19, 2015 by ptjones

[murphy]

Every 10° F drop in ambient temperature drops the pressure in your tires by 1 psi. That means increased rolling resistance. Colder air is more dense which increases the drag. It takes energy to push that air out of the way.

[hybridbear]

Sixth topic: ICE behavior

 

I also monitored some additional ICE operating parameters that I had not previously observed. While my wife was driving I had lots of time to observe the behavior of the car. I monitored the AF Ratio commanded & the actual AF ratio along with Spark Advance and VCT Advance.

 

VCT refers to Ford's version of VVT. I believe this is how Ford makes our ICE follow the Atkinson cycle. A negative VCT number (retarded timing) means that the intake valve is staying open for that many degrees of the rotation of the combustion stroke, allowing air back into the intake.

 

The AF Ratio was about 14.8 or 14.9 when at high elevations using 86 octane gas from gas stations at high altitudes. At lower altitudes the AF ration was bout 14.5 or 14.6. The car would go to a richer mixture when under heavy load (14.3 or 14.4 at low elevations and 14.5 or 14.6 at high elevations).

 

Another thing that was very interesting to observe was the spark advance. Under light load conditions (cruising at 65 MPH on flat terrain) the ICE only needs to produce about 20 kW to propel the car. The car is in negative split mode as described above. Typically the spark advance was about 30 degrees at this level of load. The RPM was usually around 1900-2000. The VCT advance was about -20 degrees.

 

Under higher load conditions (ascending a grade at 65 MPH) the ICE was producing 30-40 kW and was revving to 2500-2900 RPM. At the higher load conditions the spark advance decreased to only about 15-20 degrees. The VCT advance became more negative, more retarded, to about -35 degrees. This means that under a heavy load the car keeps the intake valve open longer to allow more air back into the intake manifold and the spark was advanced less, meaning that the ICE was waiting longer to fire the spark to burn the air & fuel mixture.

 

When the ICE would first shift from a light load to a heavy load the spark advance would momentarily drop to almost 0 (3-8 degrees usually) and the VCT advance would go all the way to -38 to -40 degrees. When the ICE would first start it would follow a similar pattern and then stabilize within 1-2 seconds.

 

I don't know a whole lot about how ICEs work so perhaps others who know more can further explain what's occurring here.

Sixth topic part two: ICE behavior, elevation & fuel octane

 

Going south to California we really start climbing in elevation after passing through Kansas, Oklahoma & Texas. I believe that in Oklahoma the gas was still 87 octane. However, in Albuquerque the gas was 86 octane. We drove on the 86 octane gas south from Albuquerque up through the mountains and then down to Phoenix. Then we filled up with 87 again in Phoenix. However, none of those tanks were full tanks. Coming north we filled up with 87 octane in Phoenix and were running that up the mountains to Albuquerque.

 

I noticed that the ICE behavior changed running 87 octane at higher elevations instead of 86. With 86 octane the spark advance would drop down to only about 5-8 degrees under a heavy load. Running 87 octane it stayed at 30 degrees under heavy load and 40 degrees under light load. Thus I decided to fill up with 88 octane today in Albuquerque instead of 86 octane. It was only $0.10 per gallon more so it cost about $1 extra to try this experiment.

 

So far this morning I'm seeing similar behavior. The spark advance is about 20-25 degrees at 35+ kW and 30-35 at 25 kW and 40 at 16-20 kW.

 

I've tried to research the interaction between octane and spark advance but I'm not fully understanding it. Why would the higher octane at high elevations lead to more spark advance? Is that a good thing or bad thing?

[hybridbear]

Every 10° F drop in ambient temperature drops the pressure in your tires by 1 psi. That means increased rolling resistance. Colder air is more dense which increases the drag. It takes energy to push that air out of the way.

hybridbear great job! From all the info that you accumulated can you come up with an explanation why we lose 2mpg for every 10*F drop in temps from 70*F?

Murphy is right on the money with some contributing factors. I've watched our tire pressures drop while the temps drop as we drive. Additionally, the peak transmission fluid temp drops about 10 F for every 10 F drop in ambient air temp. I commented on this in post 2 of this thread.

First topic: grille blocking

The transmission fluid temp only could reach 115 at 0 F ambient temp. The maximum temp increase for the eCVT has thus far increased linearly as the ambient temp has risen. Thus at 40 F ambient the transmission fluid reached 145-150 F.

At 70 F the transmission fluid temp reached 175 F. Today at 40 F it's only getting up to 148 F. The transmission fluid is a major contributor to internal friction in the eCVT. The colder the transmission fluid, the more friction internally within the eCVT which thus requires more power to overcome.

[hybridbear]

Seventh topic: maximizing ICE temp without overheating

 

On our last day in California we went to Joshua Tree National Park. Entering the park from the south you do a pretty steep climb at 35-45 MPH speed limit. This type of climb causes the ICE temp to increase more so that during a similar climb at 55-65 MPH. This caused the ICE coolant temp to reach 225. The highest peak we saw was 227 F. The grille shutters begin to open at 215 F. At 225 F the ICE fan came on and the grille shutters were about half open.

 

The ICE also began a weird pulsating behavior. What I mean by that is that while the ICE was running it wouldn't run smoothly at a nearly fixed RPM & power output. I'd be driving with a constant pedal pressure and the wheel kW would be fairly constant. But the ICE might rev up to 2700 RPM at 28 kW of power and then it'd drop down to 2000 RPM and 20 kW of power. The traction motor from the battery was constantly adjusting to make up the difference. Once the ICE temp dropped under 220 F this went away. I have experienced this in the black FFH after extended highway driving through mountains when pulling into a city and having the heat sink effect increase the temp of the ICE coolant. It happened in the FFH without any grille blocking. It appears that above 220-225 the ICE begins this behavior.

 

I tried removing grille blocking but this didn't do anything to reduce ICE temps because car doesn't open the grille shutters or turn on the fan until it's already this hot.

 

Throughout California & Arizona there are signs before steep grades saying "Turn off A/C to avoid overheating". I began thinking about this yesterday and I realized that in the FFH you want to turn ON the AC to prevent overheating. When you turn on the AC the car opens the grille shutters and turns on the fan to pull air over the radiator for the AC. While my wife was driving up the mountains leaving Phoenix yesterday I watched the ICE temp and I turned on the AC when the coolant would get over 215. Within a few minutes the coolant temp would be down under 200 F even while the ICE was working at 40-50 kW to pull us up the mountain. Since it was cool out and we didn't need AC I would then turn it off and let the ICE warm back up a bit until it reached 215 again.

 

Today with temps in the upper 30s we climbed from 4900 feet in Albuquerque to about 7000 feet and the ICE temp didn't even reach 190. At a stop I'll be putting most of the foam back in the grille to see if we can get the coolant temp up closer to 200 F today.

 

Turning on the AC not only cools the ICE but it also cools the electric components and transmission fluid. While there are various radiators under the hood, there's only one cooling fan. Thus, turning on the AC and thus the cooling fan not only pulls additional air flow across the AC radiator & ICE radiator, but also across the transmission radiator and motor electronics coolant radiator. The motor coil temp dropped by 15 F while the AC was on. The transmission fluid temp decreased by a similar amount.

Edited January 18, 2015 by hybridbear