Hi everyone! Long time lurker, first time poster! I got my TCH 2 weeks ago, and recently have been trying out Pulse/Glide methods while minimizing the battery usage like I've been reading about.

It sounds like the Glide mode, where you are in Drive with no arrows going to or from the battery, is where you want to be, but like other TCH owners, I find this nearly impossible for more than a few seconds.

However, shift into Neutral, and all the arrows vanish! The engine can shut off in Neutral but I haven't tried this more than a couple times. I shift back into D when braking for regen since I didn't see any regen happening in N.

The only issue is shifting between D/N frequently may wear the transmission. I guess my question for everyone is, do you P&G your TCH, if so, how, and otherwise, is anyone getting better than 36-38mpg in stop&go city/urban driving? My problem is, in my town, everyone drives 50 MPH on 35-45MPH streets!!

 

Shifting to N simply breaks the electrical connections to MG1 and MG2 (the two electric motor/generators). That is the reason you don't see regen braking in N, nor will the battery charge in N. There is no mechanical component of N to wear out (other than the shifter itself I guess). You don't want to spend a lot of time in N for this reason, but whether it has short term advantages like in glides, I'm not sure... Also, because of the way the 2 MGs are mechanically connected to the engine, I'm wondering if there is a max speed in N. Over 42mph the ICE must spin and normally MG1 functions as a starter motor, but if the MGs are electrically disconnected I'm not sure what would happen.

 

I don't recommend the Neutral thing. I am no expert, but I suspect that you are also killing your regenerative braking when you do that, so you now have TWO actions to take in panic stop -- Shift and then brake, so the delay could be critical. Also, B position utilizes more of the engine compression braking, which decrease mileage, recharge energy and increases engine wear.

City driving at 50 -- no probelm. I have A trim, so I don't know how it looks on nav display, but wait a little before leaving the light to open up some space. Accelerate smoothly and fairly agressively so that both drives are on until up to just above 50. Back off on the pedal until you feel the traction moter cut back in on the low end. (In my car the MPG gauge suddenly "dives" right to 60). Maintain the glide with a little pedal if necessary, but keep the MPG gauge under 40 (it takes a light foot to do this). It works, as you can see from my signature -- that is a lifetime (albeit small one) mileage from the time the TCH was new.

Glide happy!

 

Dan, I don't even know if P&G is possible in the TCH. I don't have a nav screen and the MFD on the dash always shows arrows going somewhere. I don't even bother.
BobB, Your right on. 45-52 mph is the magic speed for this car. I usually accelerate up to 55mph, back off slightly on the pedal, then at 52mph (on the dash not my gps or ScanGauge) the car goes into what I believe is the "heretical" mode. My ScanGauge says I'm getting 75-110 mpg! I can usually sustain these numbers for several miles. The beauty of driving in this mode is that it doesn't really drain the battery like driving in the EV mode does. For the first 150 miles on my current tank my MFD said I was getting 55.6 mpg using this mode and judicious use of the EV mode.

-Ed

 

My commute to and from work consists of hills and downgrades. Going to work, I end up getting a lower FE than coming home. I have found that the elevation is higher at my work than at my home. Anyhow, I have found my TCH sweet spot is around 55 mph, and sometimes a little higher. If I dip down to below 50 mph, I find that I cannot even attempt P&G, and my FE drops a lot. Since there are so many ups and downs on my trip, if I keep a steady speed, I seem to get the best FE. My MFD shows around 35-37 mpg when going to work. When coming home, it tops out the 40 mpg.

I haven't read where anyone questioned the transmission on the TCH. I sometimes wish I could "downshift" the transmission to lower the rpm's and increase the FE. If I maintain a certain speed on a level surface, the transmission does switch after a bit, and my FE starts to increase, I would just like it to get there faster. Perhaps I am doing something wrong, and with all these ups and downs, I am not sure the car can "learn" my driving style.

 

Jason, There is a way of kicking the camry into sort of an overdrive. Toyota calls it the "energy re-circulation mode" aka "heretical mode". I find that 45-52 mph on level ground, with a fully charged battery works best. Outside temperature also seems to be a factor. It's difficult to get into this mode when the temps are in the 60's. However, with temps in the 90's, as they are now here in Florida, it doesn't take much to get the car cruise at 80 mpg. Here is a great description of it. http://priuschat.com/index.php?showt...heretical+mode
There are much more technical people on this web site who can explain it better than me. Check out some of the interesting posts by SPL, bwilson4web et al.
-Ed

 

I do not like the term "heretical mode" because it has negative implications to some people. However, Ed is right on about it's use at the mid speed ranges. In this mode the computer is taking energy from MG2 and using it to reverse turn MG1. The net effect is to reduce the RPM of the ICE shaft (just like overdrive). The objective is to get the computer into this mode under the current driving conditions. I do frequently use this mode in 60 degree weather in western Washington (State) at speeds between 40 and 55. To place the computer in this mode, I accelerate to a speed slighty above the cruising speed desired, then reduce the accelerator demand by backing off the pedal over 1 or 1.5 seconds or so (not instanteanously as that indicates to the computer a coasting condition or glide). You can tell when the car enters the E-Recirc mode becasue the MPG needle "dives" down to the peg at 60. At that point, slowly reintroduce pedal to keep the MPG range between 60 and 40 or so, and also as needed to maintain the desired cruising speed. Be patient and accept slow accelerations when in this mode because if you accelerate aggresively the computer will switch to a pure acceleration mode and remove or reduce the MG1 backfeed, a sort of parallel to downshifting. The center of the speedo panel incation that you have entered this mode is a display of energy flow from both the ICE to the wheels, and from the "battery" to the wheels. In this case the battery graphic does not represent the battery, but is a graphic representation of the MG2 to MG1 electrial interaction.

To drive the TCH (or any Toyota Hybrid) for maximum FE, I thnk it is imperative to understand the PSD. I recommend serious study of the excellent diagrams and animations on the links in Ed's post above.

 

I'm not sure but I don't think driving in neutral is a good idea. For example at least 1 generator is always connected to ICE (MG1??) and there is no way around it, so lets say you start going down hill and at 35 MPH switch to neutral, what happens when you speed goes above 42 MPH ? IS the ICE going to start up even in neutral or you're going to overspeed MG1 if ICE stays stationary??? And what happens to all that electricity generated in MG1 when battery is not being charged (according to manual battery is not charged in neutral even if ICE spins) suggesting the electrical connection to battery is not maintained. There is also a warning in a manual about towing TCH with front wheels rolling on the ground and towing would be very similar to driving the car in neutral down the hill. I would think driving in neutral on the flat road, where the speed would never increase would be fine, but now you're switching transmission back and forth, much more than maybe it was designed for and coming to that downhill where it almost begs to let the car roll in neutral brings that overspeed issue again.

 

I don't claim to be an expert on P&G, but from my feeble attempts, I could never get the TCH to glide for more than about 3 seconds. I haven't driven a Prius, but I have to wonder if it is easier in that vehicle.


If anyone out there can consistently P&G this these TCH's, you have my utmost respect - you must have the patience of a saint! I didn't have the patience to try for more than a few moments. I wonder if this is why my average mileage thus far is 34.2?

 

This thread and the links contained herein from Ed are the best information I've read about maximum FE for the THC and Prius.

Awesome!