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Anybody know if / where a list of the RAV4 Hybrid warm up S-States might be posted?
I have looked around this site, as well as Googling overall web - and no joy.
As much as people refer to them - I thought they would be easy to find.
 

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Could one of you knowledgeable people explain to us Luddites what S-States are?
 

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I assume the topic is about the thermal states in the HV system. There are 4 states as I recall, and they are based on the ICE block temps. They are open loop, closed loop, kinda warm and completely warm. (The terms are mine). There may well be further delineation of those states.
 

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Perhaps use hybrid assistant app and reverse engineer those temps because current s1-s4 state (If I remember right ) is being displayed.

Starting off kinda warm or better seems to do wonders for 'since start' fuel economy.
 

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And this list is of practical importance because?
 

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On the ecomodder forum someone preheated the ICE;

"Success! Stage 4, 70˚C engine coolant temperature, in the garage in 40 minutes.

And a record commute: 4.3 L/100Km (54.7 mpg) my old record was 4.8 (49 mpg) and my average without preheat was 5.8 (40.5 mpg)

KWH and costs TBD.

Percent better: 25

Approximate gas savings per tank (assuming all island driving): $10"

Pre-heating the Prius Transaxle and Engine for better fuel economy - Page 7 - Fuel Economy, Hypermiling, EcoModding News and Forum - EcoModder.com

I think it was 750W for 40 minutes, don't know what that would cost in our area.
 

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Pre-heating saves little or nothing, since the cost of the electricity PLUS the cost of the heating hardware is never recovered.

You can just let the car sit and idle till the same temp is reached and see similar savings on the commute, with similar heating cost. Generally that means letting it idle till the first time it shuts off.
 

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Pre-heating saves little or nothing, since the cost of the electricity PLUS the cost of the heating hardware is never recovered.

You can just let the car sit and idle till the same temp is reached and see similar savings on the commute, with similar heating cost. Generally that means letting it idle till the first time it shuts off.


Whats the theory behind that, how is it better than just driving away immediately? Gonna try that btw, Thanks!
 

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Whats the theory behind that, how is it better than just driving away immediately? Gonna try that btw, Thanks!
This was analyzed and repeated many times over at the Prius forums. If you drive in open loop mode for 2 minutes you suck down several times more gas than if you let it idle for the 2 minutes it takes to warm up to closed loop. The average MPG for the trip is higher than if you just take off cold. The gain is comparable to using a block heater.

In hot weather it makes no difference because it pretty much starts in closed loop mode.
 

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My previous car was a Gen II Prius, and I studied and experienced all the HSD stages of operation (s1, s2, s3a, s3b, and s4). They were temperature-dependent, speed-dependent, and brake-dependent. To maximize economy, it seemed desirable to spend as little time in stage 3 as possible. The only way to get out of S3 and into S4 was for the engine to be above 163 degrees, and to be stopped with the brakes applied for 5-10 seconds. Seemed like a ridiculous requirement to be stopped with brakes applied to change stages. S4 was normal full hybrid operation which achieves the greatest efficiencies.

Just googled it, and the Gen III Prius stages are different. And I believe that the RAV4 Hybrid must be similar to the Gen III Prius.
For Gen III Prius, it seems as if it was easier to get to S4 (instead of requiring all-stop and brakes applied for 5-10 seconds, it only requires accelerator off (gliding) for "several seconds".
https://priuschat.com/threads/gen3-warming-up-stages.76501/#post1068435

I have no idea what the stages are for Gen IV Prius, or even if they apply to the RAV4.

The key takeaway, though, is that knowing the conditions to move from one stage into another can help you achieve better gas mileage. But, to truly take advantage of that, you have to be able to monitor engine temperature precisely, which you cannot do without a special device (like the ScanGauge). In my previous Gen II Prius I often monitored engine temperature and strategically chose when to come to a complete stop to allow transition into S4. It seemed to boost my efficiency by 3-4 MPG --- but I think it's very dependent on the type of driving, distance and terrain.

I haven't actually tested all the stages in the RAV4 Hybrid to confirm if they match the Gen III Prius, but hope to do so soon.
 

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I expect that the MPG differences from all the above are considerably less in the Rav4 than in a Prius. Maybe 1/2 as much.

Prius MPG can vary greatly with pretty small changes in conditions and driving. Not so much with the RavHV. In fact my MPG with the RavHV is so completely boringly consistent across a variety of conditions, I gave up even tracking it at all. My old Prius used to reward me for small things with higher MPG. Not so now.
 

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I read that prius and highlander users have a ECT hack that spoofs temperature readings so that the ECU goes into higher S-states yielding better MPG.




Skickat från min iPhone med Tapatalk
 

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And voids your hybrid system warranty, engine warranty, etc.


Minor detail ;)

Btw it seems like a start where Cooleant temp is above 40C skips the force start of the ICE. I had my car sitting for approx 5 hours and was able to keep temps up by using my engine block heater. The mileage instantly went to 48-50 range after 5-6 miles compared to 35-40.

I turned it on several times to read temp with my scangauge, whem it was 43C I drove away in EV mode on my usual commute to measure
 
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