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I've noticed that when I am stopping from 45 or 50mph in 5th and trying to use just regen to stop, regen dies at 1000rpm, so I tried downshifting to get more regen (still lots of time to come to a stop), but nothing, guage just nills out.

Have tried at various rpms, whenever I downshift from regen braking, it won't regen at all. UNLESS I tap the gas after downshifting to get the charge to come back on, then apply the brake again... then it regens just fine, but kind of kills the point of using the brakes :?

I get the same results no matter what gear or speed I start from when I start braking, once I downshift it won't regen until I tap the gas...

Alternatly, if I have been coasting down a hill in nuetral, going into gear it won't charge until I tap the gas.

Anyone have this issue? Or is this normal? Hardly seems like one could get maximum regenerative braking since from 5th the regen dies at around 30mph.

Thanks in Advance,
--Ash
 

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Sounds to me like your taking too long to downshift. I've seen exactly what your experiencing, also if the ABS is triggered it will cut regen until you tap the gas again. When you down shift try matching the engine rpm to the gear so you can downshift quicker and it should be fine.
 

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Mine does this as well and it's normal to my knowledge. There is one way to get around it - downshift without hitting the brakes. The only problem with this is that it will kill the syncros on your transmission when you downshift like that. You must double clutch the downshift in order to save the syncros. There are a few how-to's on this subject if you Google it but the basics are: when in gear, push clutch in and shift into neutral, let off clutch and blip the throttle to rev match the next gear down, push clutch back in and downshift. When done right, you will feel the most smooth shift you've ever done and it'll go effortlessly into the next gear.

I can use this method most of the time unless I really have to stop fast. When coming to a slow stop from the highway, you can even use the brakes down to 35 or so, doubleclutch downshift (probably into 3rd ~2700 rpm) and then take 3rd gear down to 21 mph where you can go straight into auto-stop. Usually downshift 2 gears to make it worth your while.
 

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I have never experienced the strange behaviour you described.

- Coasting downhill in neutral uses more fuel than engine braking
- Double clutching to downshift is good, but a proper heal and toe downshift is just as easy on the syncros and much faster.
- When I heal and toe downshift I get full regen as soon as the shift is completed which takes less then 1 second. (heal and toe = pressing the brake and blipping the throttle simultanously with the right foot)
 

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kapps said:
Mine does this as well and it's normal to my knowledge. There is one way to get around it - downshift without hitting the brakes. The only problem with this is that it will kill the syncros on your transmission when you downshift like that. You must double clutch the downshift in order to save the syncros. There are a few how-to's on this subject if you Google it but the basics are: when in gear, push clutch in and shift into neutral, let off clutch and blip the throttle to rev match the next gear down, push clutch back in and downshift. When done right, you will feel the most smooth shift you've ever done and it'll go effortlessly into the next gear.

I can use this method most of the time unless I really have to stop fast. When coming to a slow stop from the highway, you can even use the brakes down to 35 or so, doubleclutch downshift (probably into 3rd ~2700 rpm) and then take 3rd gear down to 21 mph where you can go straight into auto-stop. Usually downshift 2 gears to make it worth your while.
I don't quite understand why this "double clutching" is better for the syncho. How is this better than holding down the cluch while you match revs? (other than, I suppose, both sides of the clutch would be "up to speed" instead of just one side)
 

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Foxpaw said:
I don't quite understand why this "double clutching" is better for the syncho. How is this better than holding down the cluch while you match revs? (other than, I suppose, both sides of the clutch would be "up to speed" instead of just one side)
Double clutching allows the entire transmission to get up to speed. When you don't double clutch, even when rev matching, the whole momentum of the car is being transferred onto the syncros. While you can just shift regularly, your syncros will wear prematurely (I'm not sure how strong the Insight's syncros are). Maybe they can take it for well over 100k miles but maybe they can't.

Rev matching will help and I reccommend doing it if you don't feel right double clutching. It's just that if you know how or are interested in double clutching (like I was), just try it.
 
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Hi Kobushi:

___Your Insight is performing normally. The question is do you really need regen all the way to a stop? Even while downshifting into third or second to maintain regen, you will still lose regen at the 1,000 RPM and below. Once regen and fuel cut is extinguished below 1000 RPM, you should be costing as close to your final stopping point as possible for max fuel economy and minimal use of the mechanicals. Hopefully you are also keeping your SOC up so Regen won’t be needed anyway.

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:2f7q4rps][email protected][/email:2f7q4rps]

 

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Guillermo said:
- Coasting downhill in neutral uses more fuel than engine braking
How?
 
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Hi Bfivelover:

___Because during regen, you are also in fuel cut. Switch your FCD to km/h and look at the l/100 km instantaneous meter. During a coast with regen, fuel cut will place the meter at 0 l/100 km whereas a simple coast in neutral will place it at ½ - ¾ l/100 km at 50 mph and below.

___There is a trick to this as well however … If you are at a high SoC, a longer cost w/out regen and fuel cut will give you a higher overall fuel economy if you can cost down to darn near 0 mph w/out Regen and fuel cut. An example. I have a long shallow downhill coming into a tollbooth at I55 and I294 while Northbound on I55 here near Chicago. I can enter the ramp from I55 at ~ 55 mph and let her coast all the way to the toll booth ~ ¾ of a mile away and hit the gate at < 15 mph. There is a slight uphill grade in the middle of this coast to clear the overpass. If I allow regen w/ fuel cut from 55 mph, I will only make it to the slight uphill overpass before the toll both and have to step on the pedal to get over the hump and back to 25 mph for the rest of the coast down to < 15 mph at the gate. With a simple coast, I have enough momentum to clear the overpass and coast the rest of the way in. The latter (simple coast in neutral) provides a better overall gain in fuel economy after 47 miles then the former (fuel cut w/ regen and small acceleration to overcome the overpass). When there is little traffic, I actually hit the ramp at 50 - 55 mph and simply turn the ICE off via key, reboot her with one click forward, and coast all the way into the booth without an idling ICE. I almost always have 19 of 20 bars showing so I don’t need the regen and the last technique works the best for maximum fuel economy of course ;)

___Good Luck

___Wayne R. Gerdes
___Hunt Club Farms Landscaping Ltd.
___[email:3bxt21nh][email protected][/email:3bxt21nh]

 

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Just use third gear when ever you want to regen when coming to a stop. It's not too low for highway speeds and regen will stop around 20MPH which is right about where autostop kicks in.
 
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