08 vs Previous years and programming of drive train.
Created March 29, 2008, at 2:54 pm by ranger1
I read in a review that said the 08 FEH get 14% better economy due to changes in programming of how the hybrid system works. One change was said to be a smoother transition between gas/electric. The other increased efficiency of the engine. Are there actual physical differences between the drivetrain of an 08 and previous generations or is it all in the computer programming? If it's the programming could earlier modals not be re-programmed?
Is one change the engine 'always starts when first starting the vehicle(from manual)'? I further read that Ford engineers did this, even tho the engine might not always need to start on first start-ups because North American consumers are used to their engines starting when they turn the key. Or in other words "We're all total idiots who would not get used to the engine NOT starting when we turn the key!'
My apologies if this has been discussed before!
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3 years ago
Hi Ranger
There was an improvement in FE in the '08 FEH/MMH over the older models do to programming as you read. Many more drivers were reporting better mileage with average driving skills than in the past. Most if not all the improvements are because of PCM programming. However, you just can't reprogram the older models because each vehicle has an "AS Built" PCM program that's specific for the equipment and other programmed modules installed at that time. In other works, just reprogramming the PCM to the '08 would screw-up how the older modules and systems work.
There are a number of excuses Ford used in designing the engine to run before you can go EV, but newer models like the '09 will change as hybrid owners are catching on to operating them. For instance, the '09 engine will start and shutdown more often and have a better fuel-cut when you let off the gas pedal. Ford was concerned in the past that this would confuse the driver and didn't want wear out the eCVT quicker. Now Ford knows the eCVT is built solid with FEH taxi's having over 200,000 miles with no problems.
The '09 FEH/MMH will begin some new physical changes in the eCVT, engine, and we might see a change in the HV battery design to reduce cost.
GaryG
3 years ago
The issue with the ICE "engine" having to "start" when you turn the key on may also be related to emmission standards.
3 years ago
I own a 2008 FEH and have also wondered why the ICE always comes on when you turn the key, even if it is fully warm and has only been turned off for just a few minutes.
I have heard that it is to make sure the engine oil and coolant are circulating and at proper operating temperature, that the catalytic converter is fully warmed up and that the battery charge is topped off.
I hadn't heard the one about not confusing neophyte hybrid drivers and I can't really quite see that, sounds silly.
I don't understand the eCVT explanation, as the vehicle is operating on electric mode at low speeds whether the ICE is on or off, particularly in reverse.
3 years ago
Hi mdensch
In the past few years, I've read so much from articles, Ford hybrid patents and the workshop manuals on why Ford designed systems the way they did. Ford Engineers and employees have held classes on the FEH to explain much of owners questions on their system design and how to drive for the best FE. My friend Wayne Gerdes took notes and posted them on his Website:
http://www.cleanmpg.com/ The thread is here:
http://www.cleanmpg.com/forums/showthread.php?t=125
Many things have been wrongly posted that have added to the confusion on these sites. I've been guilty of that many times myself, but when I discover I was wrong, I try and repost the correct information. Your comment above about the battery being topped off is incorrect for example. The engine can shutdown to go EV with a battery between 41.6 to 42% charged.
Ford Engineers have designed a warm-up strategy for the FEH/MMH which when I first notice it while driving, I thought it was to let the oil circulate to prevent wear. Wrong!!!!!..... I found the Ford Hybrid patent on this strategy and found the reason the engine idles while the electric motors provide torque to the wheels during warm-up. The PCM retards the timing and holds the engine at an idle to heat the engine and CAT Converter quicker for emission purposes. Now that I understand how the Strategy works, I've improved my mileage.
Here is an article that I got some of my information recently:
http://www.greencarcongress.com/2008/02/ford-previews-n.html
"Markaby also noted that Ford has sold 70,000 Escape hybrids to date, and that some units have reached 200,000 miles in service with no service problems."
"Idle-stop and start events are much quicker, and enable greater efficiency with as many as two times the starts and stops in a given driving cycle as the previous system. The quicker engine shut-downs and pre-positioning (for the next start) also reduces O2 build-up in the engine’s catalyst. Decel Fuel Shut-Off (DFSO) mode and electric-only mode have also been expanded."
3 years ago
All in all tho, in regards to 08 improvements, I think what it would take me to trade up to a newer model in the future would be a marked improvement in the capability of the battery for electric drive only and/or plugin hybrid!
Electricity here in Manitoba is government run, hyrdro produced (quite green) and cheap! My previous location, Alberta Canada electric bills, were 3x what I pay here and that was for a smaller house than what we have now. Some folks have said that this would be the cheapest place in N. America to power an electric vehicle.
3 years ago
Ranger, why do you think I'm waiting for the '09 FEH and the '09 Prius? I've read that the '09 Prius is being designed so the plug-in Lithium Ion battery can be installed in the future. The '09 Prius will be able to go EV at 62mph for a coast and when the lithium Ion is up graded, it might be able to cruise in EV at much higher speeds than it does now.
It also appears that the '09 FEH, Malon, and Fusion eCVT is being upgraded for higher EV speeds.
"Variable-Voltage Converter (VVC). The new powertrain’s inverter assembly utilizes a DC-DC buck-boost converter, which Ford refers to as a Variable-Voltage Converter, to step up the voltage potential of current from the battery pack before it is synthesized into a three-phase AC waveform to power the transaxle’s two electric motor-generators."
"High-Efficiency Transaxle. The maximum RPM of the new transaxle’s permanent-magnet synchronous motor-generators has been increased, and a new low-drag transaxle fluid has been formulated. The higher available voltages from the variable-voltage converter allow greater torque at higher speeds. Typically, such voltages also enable a more efficient recuperation of kinetic energy via regenerative braking."
"Stepping up voltage allows the powertrain to produce a given output using less current, which reduces resistance losses and increases efficiency. It also allows the manufacturer to use a smaller, lighter battery: the 275V, 5.5Ah, 27 kW peak power NiMH battery pack used in the new Fusion/Milan hybrids features improved cell chemistry, and is more compact, for example, than the 2005-2008 Escape hybrid’s 330V battery pack."
http://www.greencarcongress.com/2008/02/ford-previews-n.html
What I think this means is the FEH may or may not keep the present 330V battery. If the new VVC is installed in the '09 like I think Ford is saying, this could allow higher speeds in EV than the present limit of 40mph. This would allow me to adjust my P&G techniques for better mileage and faster speeds. Also, the present battery A/C could be deleted if Ford changes to the newer battery. Not having the compressor running for the battery would also increase my mileage here in Florida.
I'm hoping an upgrade like the '09 Prius that will allow a plug-in lithium-Ion conversion, can be added in the new '09 FEH/MMH at a later date when the battery prices comes down. Toyota is interested in taking the after market plug-in retrofit business away it sounds like, and I hope Ford thinking the same thing. What's holding both Manufactures back now is the cost of the battery.
3 years ago
Oops, sorry, guess I'm not that 'up' with the techno talk. I have to admit I did a bit of an LOL reading this: '...utilizes a DC-DC buck-boost converter, which Ford refers to as a Variable-Voltage Converter, to step up the voltage potential of current from the battery pack before it is synthesized into a three-phase AC waveform to power the transaxle’s two electric motor-generators....' Especially the buck-boost converter part. I almost rolled off my chair.
To summarize, I take it that the buck-boost converter is somehow involved in saving one's bucks when filling up at the ol'pumps!
Hope I'm not treading dangerous water hear, just teasing a bit and dearly hope you're not offended, but on first read it was rather funny. Perhaps the terms are more familiar to electrical engineers than retired park rangers!
3 years ago
Ranger, your not treading dangerous water at all. It may be that Toyota used the word "Buck-Boost" for the reason you stated. The term Ford used "Variable-Voltage" just applies to more than converters I think. The bottom line is, if it does save bucks, I think we all don't care what they call it. I think "Break Big Oil" should have been the name Ford created for their converter. Surely, a "Break-Big-Oil Converter" would be something that would catch my eye.
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