Pulse and Glide plus Warp Stealth in the Prius II for maximum FE …

[jkp1187]

I'm posting just to say that this is an excellent description of pulse and glide, and that I didn't really understand what the concept was until reading the first post. The glossary entry really should link to (or perhaps be replaced by) that post.

[Wilson Chan]

Hi Wayne and all HMs,

I come from Hong Kong and drive Prius for half year. This is a wonderful thread which teaches drivers to take the most advantage of Prius' parallel hybrid system in achieving FE.

I am still at learning stage and my reading increased from the original 45MPG (5.2L/100km) to 53MPG (4.4L/100km), certainly still a long way to go for even reaching the threshold of 60MPG! Given the nominal capacity of the fuel tank as 45L, here we each strive to make an own record of travelling 1000km with a full tank. To achieve this, one needs to be 4.5L/100km in theory for the very last drop of petrol. In practice, one has to be 4.3L/100km or lower. Not sure if there's any similar play for those in MPG.

To help me have some breakthrough in HM, here comes the questions:

- To start the car from stationary, the initial FE is terribly poor and FE improves gradually while the speed is increasing. So to avoid ICE on at low speed, I pressed the EV button for starting. When the speed reached 30MPH, EV would be off anyway. Bad point was the pack then probably left with only 3 or 4 bars which was not favarable for P&G and HS P&G. So now I used to start with EV button on but depress it when reaching 12-15 MPH, hoping to avoid the ICE starts from stationary, yet not to draw too much from the pack. Does this make sense in terms of FE?

- My parking space is on 4/F. So when returning home, I press EV button and drive up as fast and safely as possible. This usually left with 3 or 2 bars when parked. The next time I drive out, ICE usually turns itself on due to low SOC or temperature. But I am on the way down and hope that regen will rise SOC quickly while ICE is warming up. Again, does this make sense? Or should I better go up 4/F with ICE on?

- In warp stealth (HS P&G) gliding, the pack used to keep ICE spinning. In P&G gliding, if I press pedal slightly more, yellow arrow appears and it seems to help keep the speed. Is this really the case? So this time does the pack drive the ICE or keep it spinning?

Regards
Wilson

[rickkop]

I understand that this forum is mostly for Prius owners but, is this pulse and glide something I can do with my 09 TCH? I have read this and am trying but am haveing a very hard time getting the screen with the power only going to the engine and the battery only? I see a lot of peopl have a scanguagII. Would this help me and if so how. Thanks, Rick

[xcel]

Hi Wilson:

___A good rule of thumb is to bring the Prius-II and –III up to 15-mph under EV and than bringing the ICE online. You can go higher but the SoC payback is harsh as you well know. I use 15 mph under most circumstances and it has proven its worth time and time again.

___End of the day SoC is a hard one. Here in the US, the ICE will start and not supply any power unless a high percentage of throttle is demanded. The Prius-II will accelerate on the pack and MG2 even while the engine is idling at 1,200 + RPM during to warm-up to achieve S1. It is absolutely ridiculous that it works that way but that is the way the Prius-II was designed for us here in the US to meet the strict emissions standards more than likely.

___During WS, the pack does indeed keep the ICE spinning over. It is a limitation of HSD to protect or limit current on MG1 when trying to start the engine while it is above 6,500 RPM at 41 mph. We have a technique we call Warp-Neutral wherein we engage N before we reach 41 mph and let it increase up to 62 mph (MG1 spinning at 10,000 RPM backwards) without the pack spinning up the ICE. This can only be used on downhill’s as you will not accelerate above 41 mph without the assistance of gravity.

___There are some limitations that can be exceeded with the above but that is best left to direct discussions with those in Japan that actually designed MG1 including its actual capabilities

___Rickkop, CleanMPG is about all vehicles including all-electrics to 18-wheeerls. This thread is about HSD and your TCH can use similar techniques. To glide however, you will have to run N as the dead band is simply to small to control with your accelerator. If I ever get the opportunity to review a TCH (I really should get on this but Toyota has always been out when I have requested one), I will write-up a TCH specific technique section. You will be looking for 18 TPS and 18 IGN via a ScanGauge-II for 60 + mpg highway driving and using P&G around town with N to hold your glides is what it comes down to.

___Good Luck

___Wayne

[rickkop]

Wayne,
I'm sure there a lot of us TCH owners out there that wish Toyota would get a TCH for you to review. Looks like if I'm going to be serious about mileage I better get myself a scanguage. Thanks for the help, Rick

[xcel]

Hi Rick:

___No problem and like I say to many TCH owners in person, you have one heck of a nice automobile and most importantly, enjoy it

___Good Luck

___Wayne