A few quick notes on the Prius-II from a non-Prius-II owner …

Discussion in 'Toyota' started by xcel, Aug 20, 2007.

  1. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi All:

    ___Dead stick glides work in the Prius-II just as they did in the Prius-I so the warm up hit can be managed with the right kind of initial route.

    ___The drivers seat bottom is a bit short for me and my right thigh is off the seat cushion while on the accelerator. I will work on a better driver position tomorrow.

    ___EV is much stronger (much less hit on the pack for an equivalent distance) then in the Prius-I.

    ___All 5-minute bars can be pegged in 63 - 64 degree temps and medium to light rain on my drive to the Interstate tonight. Not a chance of that in the Prius-I.

    ___Bluetooth … I cannot seem to upload my Motorola’s 815 address book to the Prius’ address book?

    ___TPMS ... Manual states a max 73 # tire pressure before the transducer evokes a TPMS warning.

    ___SG-II at 0% speed/distance and 0% Fuel use offset seems to be at least 10% off of the MFD :confused: I just started the SG-II calibration tonight so we shall see what comes of that?

    ___Tank was almost empty when it arrived. Drove 51 miles beyond the last blinking pip and added 12.2 gallons.

    ___Good Luck

  2. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    I can't wait for more!!

    Look out guys, here comes another 1k+mi tank!!!! :D
  3. Tochatihu

    Tochatihu Well-Known Member

    Some tall folks have adjusted Prius driver seat by replacing the front 2 seat bolts with longer, and stacking washers under the rack to get more 'tilt back'. The rear bolts must be slightly loosened for that (and retightened when finished).

    Don't mess up the fuel tank HC adsorber on somebody else's PII by overfilling, xcel :)

  4. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi All:

    ___There is a bit more to the Dead-Stick Glide in the Prius-II then the -I. I am not sure of the exact procedure just yet but somehow I was able to hold ICE-Off after a 10 second pulse/start via cycling the power button but only had to shift back into D for her to start back up without goofing around with rebooting again? I have to figure that one out as I really liked this quick hit FAS w/out the dead stick mode of operation in order to reduce the warm-up hit.

    ___Also, if you do shift her to N before the 8-second (I think it is about 8 seconds?) system check from dead cold, you can keep the ICE-Off in case you have a downhill to begin your initial movement. Sort of like a FAS without the FAS?

    ___She hates rain and it has been raining like a beast in the Chicagoland area for the past 2 + days with another two projected so she is sitting a lot more then being driven.

    ___Doug, I had a good look at the bladder details and I don’t see how anything is going to get out of that and up into the canister. When you are full, there might be another miniscule .4 gal left to top off. Sad given the European’s and Japanese do not have that #%( *#!)$ Prius bladder and another ~ 15L + is available for much further range :angry:

    ___Great to hear about a method to fix that seat height/angle given I am sure my right thigh is going to be a bit fatigued over a longer drive. In Pittsburgh, I was probably to focused on the task at hand to worry about the seat ergonomics? Would you mind doing another peer review when this is complete?

    ___JimboK, can you do me a favor and watch current flows from a 70 mph down to 50 mph WS Glide? I saw some similar action as the -I with a back and forth no-arrow glide to pack through MG1 and back to a no arrow glide while slowing gently. The ICE was spinning over at 980 RPM as it should but the mimic can be held in a no-arrow and I want to know what current flows are doing while traversing this state? I don’t think this is the case but could MG2 be involved with this High speed WS no-arrow glide to keep the ICE spun up?

    ___SG-II was only under reporting by 3 this morning vs. the MFD. The actuals were a rather embarrassing at 67.3 in heavy rain with an average speed of 51 mph but she will get her chance once the SG-II is calibrated after a quick first pip to top off fill sometime later this week and when the weather clears :)

    ___Good Luck

    Last edited: Aug 20, 2007
  5. brick

    brick Answers to "that guy."

    It has been done, and with expensive results. (Galaxee at PriusChat posted the details.) What you have to remember about the bladder is that gravity isn't the only force working on that fuel. If the tank is completely full and then fuel expands during the heat of the day, the bladder acts like a balloon and forces the fuel out of any available path of least resistance. That can be (and at least a few times has been) into the EVAP canister which gets saturated and fails. Sadly the only way to repair the damage is to replace the entire freaking fuel tank. (Another example of cars being designed for manufacture but definitely NOT for serviceability.)

    The one thing you have going for you is a long-ish commute. If you fill in the evening before heading home (or in, as it may be) and then head back the other direction the following morning you should have burned off enough fuel to overcome the expansion. But hey, what do I know...
  6. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Tim:

    ___Thanks for the details. She saw about a gallon and a quarter consumed after the fill and I will continue that practice so she is good to go.

    ___Good Luck

  7. JimboK

    JimboK One owner, low mileage

    You're asking me to go 70??? :eek: What's this world coming to?!

    I think it's in the neighborhood of 10 amps, but I'll see if I can get it onto the highway in the next day or two to verify.
  8. hobbit

    hobbit He who posts articles

    I ran across an interesting technique over on iATN for trying
    to clear the canister: get the engine idling, force the purge
    solenoid open with a scantool, and let it sit there pulling
    vapor through the intake for half an hour or more. The theory
    is to pull enough air back through the vent canister to dry it
    out, basically. Dunno if it would work on a prius, and some
    of that purge air goes through the tank between the outer shell
    and the bladder as an additional leak-detection technique [i.e.
    the system uses the A/F sensor to look for additional vapor]
    so it might take even longer than with a conventional car.
    Warp-stealth currents on the "plateau" are generally on the
    order of 10 amps, but with *very* fine foot control you can
    regulate between that and the -20 amps of regen and find zero.
    The MFD will go to a no-arrows state around 0 amps but that's
    really difficult to find and hold without a current meter.
    As regards motor torques -- never assume that anything is happening
    solely with MG1 or MG2. Torque commands are generally sent to
    both, to balance out everything going on between them and the
    engine and driver demand eventually showing up at the wheels.
    Even something simple as starting the ICE at a standstill involves
    a little back-torque in MG2 to counteract the forward spin that
    MG1 is supplying. The net result of wherever power flows to
    is what shows up as battery current, but that doesn't show what's
    going between the motors internally to the inverter.
  9. locutus

    locutus MPG Centurion

    Uh-oh, Wayne gets a hold of a P-II... ;)

    - Can you explain "Dead-Stick Glide"?
    - N within 8 seconds of powering on will indeed prevent the immediate S1. You'll still need to go through it at some point but you can prevent it on startup this way.
    - Odd, my SG with no calibration has been pretty much dead-on in terms of MPG, though distance seems to be about 1% under-reported.
  10. brick

    brick Answers to "that guy."

    I got pretty good at hitting it by letting all the way off the pedal and then just **barely** touching it to kill regen. To my butt-o-meter at ~60mph, no arrows doesn't seem to gain a whole lot vs. backing all the way off in terms of drag and glide distances. It's odd because the car noticeably "lets go" once the MFD shows a little juice flowing out of the battery. If nobody had told me otherwise, I'd think that the range was almost zero amps of regen out to something measurable on the assist side.
    Last edited: Aug 21, 2007
  11. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi Jim:

    ___Yup ;)

    ___Al, thanks for the info. I have been waiting to hear about MG2 doing its thing and holding no-arrows at 60 + down is pretty cool. Even if it doesn’t add anything, it is still cool :D

    ___Jerad, read the Prius-I review techniques. The thing that was ticking me off was the 40 mpg garbage after a mile or two. With the Dead-Stick Glide, the P-II allowed 70 within a mile in heavy rain and the SoC was holding at 4 of 8. I love the fact that the P-II’s thermos bottle brings you right into S2 immediately vs. working your @$$ off with the P-I!

    ___Tim, I was playing around with HS P&G tonight and it doesn’t work very well. I should have listened to you long ago. The SG-II was 3 under when I got home again tonight. That appears to be the offset. I will be filling from the cal on Wednesday morning.

    ___Although there is a ton of rain holding her back, the OEM moly loaded goo still needs to be changed out and I have not yet pressed everything up, the P-II just doesn’t seem to hold 75 out on the highway no matter the speed as of this write-up. A well setup P-I would hold that all day long? 100 + unmolested and at a snail pace is a gimme but holding 75 + on the highway is really throwing me for a loop :( 78.5 into the drive tonight and it was a lot of work!

    ___Good Luck

  12. Dan

    Dan KiloTanked in post 153451

    Ditto on your Yikes.

    Interesting about dead-stick glides. On my '07 Prius, the Power button will also throw the parking clamp down, so I've kept my hand off of it. I heard that it will just give you the polite beep-beep PriusII refusal to do what the dumb human requested.

    As far as S1 goes, from READY to ICE-on, comes to 14.0 seconds on my stopwatch. Very consistent. I never timed it from "D" to ICE-on, but figured that READY started the timer.

    I've also done a lot of work on SG calibration. Here's my latest results.

    Size - Closest you can get on the SG is 1.5L, actual is 1.496L. So SG overstates displacement by 0.27%

    Distance - If calibrated to the odometer, SG understates distance by 1.40% (±0.13%). This may line up well with physical distance traveled. It's been speculated that many cars overstate miles to gain more frequent services (1.4% of a billion dollar business is a lot).

    Fuel Consumption - If calibrated to the MFD, fuel consumption is overstated by 3.98% (±0.51%). This actually turns out to be pretty close to the physical consumption, since I know that the MFD overstates my tank MPG by about 4%. So if calibrated to physical consumption, it's probably pretty close to spot-on.

    MPG Calculation - A bit of math with the other two calculations (and a bit of field work) show that SG understates MPG by 5.73% (±0.76%).

    If you know how much you want your MPG calibration factors to be, there is a utility (I posted in files) that will tell you what Distance and Fuel Consumption calibrations you need to enter. Right now mine is set to Distance: 0%, FC: -5.9% which gives me (because of the inverse nature of the ratio) +6.27% adjustment to MPG. After a bit more data collection I will change my calibrations to Distance: +1%, FC: -4.5% which will yield an MPG adjustment of +5.76%

    Once you know your exact figures there is a trick in the SG FW to allow you to enter discrete calibrations on FILLUP. At your next fillup, go through FILLUP on SG *twice*. On the second FILLUP with GALLONS at 0.0, the left and right calibrations will simply adjust the calibration percent by 0.1% increments.

    Look forward to hearing what we need to be shooting for.

    Jared, your hitting those numbers with no SG calibrations? Do you find SGII to be true compared to MFD or compared to your gas receipts?

    Last edited: Aug 21, 2007
  13. locutus

    locutus MPG Centurion

    Before I had the SG I was calculating trip MPG based on MFD and TRIP A/B before/after. Once I got the SG I added a column to my spreadsheet for the SG-reported trip MPG and started recording that as well. Some 98% of the time the SG-reported has been within the error bounds of what I was doing before using the MFD numbers (recent example: MFD 73.7 +/- 6.8, SG 76.1). Over my ~20k miles my MFD has been ~2.6% optimistic, so I guess technically I should recalibrate the SG to reflect this.
  14. mparrish

    mparrish Rosie the Riveter Redux

    Never thought about that. How clever. I too noticed this understating by ~1%, and calibrated SG to match the Prius ODO. But I will probably get out and do a mileage marker test now.
  15. JimboK

    JimboK One owner, low mileage

    OK, I tried. Hit the highway after work. Had some thunderstorms on the radar several miles to the west, but I figured I could beat 'em. Wrong. By the time I got up the road to a decent WS spot, 3 miles or so, they were on me with all their fury. I'll try again tomorrow, unless Hobbit's confirmation is sufficient.
  16. JimboK

    JimboK One owner, low mileage

    OK, got 'er up to speed today for the 70-50 WS: It hovered a little over 10A, bouncing up to 14 or so at times at the higher speed. The bounces seemed a little lower as I approached 50, though it still stayed above 10.

    One of these days I'll get my data logging working and I can offer a continuous record for things like this. :(
  17. xcel

    xcel PZEV, there's nothing like it :) Staff Member

    Hi All:

    ___A few updates before heading back out to battle the rest of Chicago …

    ___This vehicle is the most frustrating vehicle a person could love. For those that push it anyway. Load is almost always up in the 70 – 85% range under any number of scenarios including steady state cruise so you cannot wring much more out of her using the tricks that work for everything else. I also believe the slower speed highway capabilities of the –I are better then the –II. The –I would hold ~ 75 at 47 – 50 whereas the –II will only hold 70. The –I would not hold squat at 60 whereas the –II will hold 60 + all day long.

    ___Pulling 99.9 over any lengthy and unmolested section is awesome in the –II but … Pulled up to the highway after 18 miles of solid P&G at 99.9 Not 18 miles later and I was down in the 78 range. After 47 miles I was all the way down to 71.3 :angry: I left the Interstate after 85 miles at 75.5 and brought her back up to 78.6 or .7 into the drive. Frustrating and infuriating to see the huge drop off on a section of highway leg like that? Temps in the high 50’s to mid 60’s did not help but I am sure I speak to the choir about temps and the Prius-II …

    ___Another weird item … On the way to work yesterday afternoon, a traffic slowdown from 60 + to almost 0 brought her SoC up into the 7 of 8 bars (light green) and I held it there for over 20 minutes. During that time, her highway FE was holding in the 75 range at 50 + mph. Once that 7th bar dropped, her highway FE dropped back into the 70 range. I just don’t know a good way to coax her into the 7th + bar range although holding her there is as simple as DWL and stay the heck off assist seen though the mimic is going crazy showing the P-II trying to dump that excess energy ASAP.

    ____Jim about WS, was there any change in current as you went from Yellow (pack to the ICE) to no arrows that you can remember?

    ___Good Luck

  18. Dan

    Dan KiloTanked in post 153451

    Wayne, I assume the PriusI and Honda's are like this, but in the Prius II SoC is a huge governing factor for me. WS is pretty easy to catch at a high 6 bar SoC, but at low 6, 5, or 4 it gets very hard to catch, and I've never been able to hit WS at 3 bars. I noticed that stuff like headlights and the climate control fan will hinder my abilities to hit WS at 5 bars as well. Once I get to the high 6 (which is where it seems to live on the HW) WS is pretty consistent, but the sweet-spot seems to move around a bit as you slow down causing me to fall off the glide from time to time. This has been what I've been concentrating on for the last few weeks.

    Another oddity is the 4th bar "shift". If you have a low 4 SoC and you pulse up at around 1600 rpm, eventually you will feel what seems like an AT shift into high gear followed by a drop in RPM down to about 1300. So it seems consitant that at low SoC the pack robs more power from the engine, so at high SoC I'd image all of the engine's power (and possibly some of the packs) is going to move the car. In the end, having the accellerator at the same position (muscle memory) will have wildly varying RPM based purely on the current SoC.

    If you have one of the XGAUGEs there are some (possibly) better LOD readings you can coax out of OBD. 0143 is said to report "Absolute Load" instead of "Calculated Load". HSD may do some funny math making "Calculated Load" vary from ICE Load. Pid 43 (mode 01) is flagged as supported so it might help. 0145 and 0147 also offer variances of TPS if your using that at all.

    Keep us posted. I'm hoping I can get my good numbers to catch up with your bad numbers soon.

  19. Right Lane Cruiser

    Right Lane Cruiser Penguin of Notagascar

    Very interesting, Wayne. I did not know the fall off on the highway was so severe... I'd be frustrated, too!! (Not that I can pretend I'd pull numbers like yours!!!)

    The fix would be some way to effectively P&G at high speed, but it sounds as though WS is completely out for that use? A low speed monster with no staying power at highway speeds? :(
  20. brick

    brick Answers to "that guy."

    Wayne - Now you understand why I'm so freaking happy when I break 60 on a 100% highway commute. Welcome to our world. ;) I think the "problem" is that the car sets the bar so high to begin with that you really have to get into the fine details of the system to make significant gains at highway speeds. I don't recall if you are using engine RPM but I consider it to be 100% essential feedback. I felt totally lost this morning since I removed the tach in order to build a better mount. I guess watching LOD is good enough for the most part but the engine doesn't start to "speak up" until you're close to the 3,000RPM mark and well out of the ideal operation zone.

    Green bars are nice while they last, although the cost is high to get them. What you experienced is most likely a taste of what a PHEV would be like in charge depletion mode. The system does its best to get rid of extra charge while you have it resulting in temporarily inflated iFCD numbers. That said, I don't think there's anything you can do to "coax" it into the 7th bar without adding a plug since it is entirely dependent on having excess battery power available. You should see the thing run with 8 full bars. Ever see a Prius run in Stealth Mode at 50mph? Wanna?

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