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I have CAN-VIEW installed on my NHW20 prius and when letting my foot off the accelerator (any stage really... doesn't matter) my Liters per hour reads zero. So correct me if i'm wrong...

a) zero fuel flow to the engine? must be controlled by MG1

b) I did not notice if i was using more amps during this mode however since my foot is off the gas I only see amps being put back into the battery.

c) I did not remember seeing this mode in the NHW11 prius although the Miniscanner was not optimized for this kind of data (I mostly used battery voltage, RPM, current and coolant temp)

d) shouldn't the engine be more "quiet" when its only propelled by MG1? There are no explosions in the cylinders right? If so it still feels like its firing even when my foot is off the gas.

e) if zero fuel flow is possible on the nwh20... then why shut off the engine when coasting? I notice it takes a good 30-50 amps of a second or two just to turn on the engine again... quite a bit of energy! Kinda of a waste if you knew you were going to need the engine again within the 5 second period.

f) I noticed when my SOC is pretty high (like 75%) or so, RPMS shoot sky high towards the 2200 rpm area and my amps are like -40. Wow the battery really loves to waste energy, heck sometimes with my foot off the gas the rpms still spin high and amps are being wasted, an extra battery would be nice... sometimes flooring it would use -100 amps and the engine is still idling at such high rpm!

g) I can't wait to convert this prius to a plug in... even if its a bunch of lead acid batteries.

So back to the question.... zero fuel cut mode on the prius bs? or only available on the hchII?


edit:
thank you efusco, you made my day!

Yes, it's true. I find that condition primarily in "hyperstealth"...ie. over 41mph. I think it takes about 6 amps to keep the ICE spinning as the 'sweet spot' on amperage seems to be about -12 compared to 'true stealth' where it's -6 amps.

There is a fuel flow cut-off mechanism that allows 0l/hr flow.

Hi Phil:

___WTH, a Prius II? Why didn’t you tell us! What kind of trade did you receive and why did you dump the -I (NHW11)?

a) Standard Fuel Cut.
b) You are in Regen, right?
c) Mini Scanner is not quite as capable as CAN-View ;)
d) MG1 spins her over above 40 during warp stealth, when spinning her up to start and probably when burning off excess SoC similar to the FEH but I am not sure about this?
e) If you do not disconnect and shut down the ICE, it is a compressor causing ICE-braking.
f) See d)?
g) DON’T DO Pb-Acid. It is a waste of your precious time and resources. Wait until Li-Ion packs are made available. If EnergyCS and HyMotion can get A123’s today, you will in the near future.

___Good Luck

___Wayne

Yes, it's true. I find that condition primarily in "hyperstealth"...ie. over 41mph.

Hmm.. my scangauge never reports 9999 when in warp stealth, always something like 200-250 MPG... is it confused? Is there really no fuel draw despite RPM > 0? If this is the case I can stop worrying about unnecessary consumption when other conditions work better to peak at something like 45-50, then WS through 39 and transition to true stealth.

Hi Jared:

___When the ICE is spinning via MG1 in Warp stealth , it is drawing air and the SG-I/II unfortunately calculates and displays a given very high fuel consumption even though no fuel is being injected.

___Good Luck

___Wayne