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2013 Rio5 EX w/ Convenience & ISG
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Discussion Starter #1
When decelerating, especially downhill, has anyone noticed how the automatic tranny downshifts thru the gears?

And at some point, it feels like the tranny 'lets go' like it goes into neutral and lets the car coast?

I live in foothill area and when cresting a long hill at 55 and approaching a faraway downhill stop, I'll just take my foot off the gas and let it coast in 'D' but I feel it gear down a few gears for a while. Eventually, the holdback just lets go and the car immediately picks up speed like it decided to coast in neutral.

It'd be nice if the car would go neutral and coast down these long hills.

Anyone corroborate? Or am I nuts? :confused:
 

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14 Forte SX Koupe,15 Soul EX,58 & 90 Rolls Royces,92 Mercedes 500SL
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When decelerating, especially downhill, has anyone noticed how the automatic tranny downshifts thru the gears?

And at some point, it feels like the tranny 'lets go' like it goes into neutral and lets the car coast?

I live in foothill area and when cresting a long hill at 55 and approaching a faraway downhill stop, I'll just take my foot off the gas and let it coast in 'D' but I feel it gear down a few gears for a while. Eventually, the holdback just lets go and the car immediately picks up speed like it decided to coast in neutral.

It'd be nice if the car would go neutral and coast down these long hills.

Anyone corroborate? Or am I nuts? :confused:
Mine does the same & I consider it normal. Don't know of any Automatic Transmission that shifts to neutral going downhill.
 

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2012 Rio SX Hatch
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391 Posts
Mine does the same & I consider it normal. Don't know of any Automatic Transmission that shifts to neutral going downhill.
shifting to neutral while going downhill would be a safety hazard, can't have a vehicle deciding when to take you out of gear.

also, you would use more gas going down the hill in neutral than you would going downhill in gear (based on design of modern car fuel systems).
 

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2013 Kia Rio EX
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5 Posts
When decelerating, especially downhill, has anyone noticed how the automatic tranny downshifts thru the gears?

And at some point, it feels like the tranny 'lets go' like it goes into neutral and lets the car coast?

I live in foothill area and when cresting a long hill at 55 and approaching a faraway downhill stop, I'll just take my foot off the gas and let it coast in 'D' but I feel it gear down a few gears for a while. Eventually, the holdback just lets go and the car immediately picks up speed like it decided to coast in neutral.

It'd be nice if the car would go neutral and coast down these long hills.

Anyone corroborate? Or am I nuts? :confused:
I get the same thing when I even pull up to a stop sign. I feel like I have to gas it a little while longer to get there. I wish the tranny would stay in the higher gear longer. I feel the same way when I use the auto-stick. As soon as the car hits a certain speed it downshifts without me telling it to. I WANT MORE CONTROL! :)
 

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2013 Rio5 EX w/ Convenience & ISG
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Discussion Starter #6
shifting to neutral while going downhill would be a safety hazard, can't have a vehicle deciding when to take you out of gear.
Eh, arguable. Darn thing decides when to cut the throttle and retard the acceleration via traction control. Can't tell how many time I nearly got creamed trying to get out of a driveway and the car gets all "no you're not".

also, you would use more gas going down the hill in neutral than you would going downhill in gear (based on design of modern car fuel systems).
That's right, I forgot. The injectors do cut off when decelerating. When you got to neutral, the injectors cuts to idle. Supposedly saves 2% fuel.

Still, they're developing technology to let the tranny disengage when in a decelerating mode.
 

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2012 Rio SLi 'Latte' 6AT 1.6GDi
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it doesnt actually go to neutral, I did a little test with the manual mode to see what it does.

I have a hill on the way home thats fairly long and decided that it'd be ideal for the test.
The speed limit is 60km/h so I was sitting just below that and checked the gear by moving the lever into the manual gate, the display said 4th. Moved it back into D and let it roll and then it 'let go'. I checked it again and it said 6th. So basically it just went into the overdrive gear to coast down, hence the feeling of going into neutral. So no stress, it just goes "ok, you obviously don't need power anymore so I'll just go into fuel saving mode"
 

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2012 Rio 5 & 2009 Rav4 Sport V6
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I hate that feeling of 'letting go' and coasting down the hill. I've been driving manuals all my life and like the feeling of gassing it to maintain speed down a hill.
 

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There's a stop sign on my way home from work.
In my 2012 auto rio, I drive down the road at between 40 and 45 towards it.
I get up fairly close, and take my foot off the gas, far enough away i expect i can coast right up to it, but, then it downshifts a couple gears and i feel a slight tug as it slows.
Very flat road.
 

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2013 Rio5 EX w/ Convenience & ISG
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Discussion Starter #10
Yes. I have a long sweeping off ramp and while decelerating it feels like its tugging and deliberately slowing the car down. I wish I could see if its even shifting gears while decelerating.

In my Scion xA manual, I just hit the top of a downhill off ramp at 55mph and put her into neutral. I'm flying along freestyle all hyper-miling it and still at 45-50 at the bottom. Not so in the Rio, I'm at 25 or so.

I think I have issues with these auto trannys. Wish my EX had a 6 speed manual.
 

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2013 Soul+ Shadow, 1970 Opel GT 1.9 CIH 4M
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142 Posts
Ams

Daddy-O

This is an interesting phenomena that I had always assumed was caused by the AMS (Alternator Management System) that comes with the ISG Package. This system is only charging the battery when descending or decelerating, and stops charging while accelerating or climbing. This regeneration process slows the car down during coasting but saves fuel by using the cars inertia to charge the battery instead of the engine.

I'm sure that the AMS Package is not the cause for all of the deceleration effect, but it must be a contributing factor on ISG equipped cars...

The overall ISG logic may be flawed when it comes to "Stop and Go" driving, but we at least get a state-of-the-art alternator and some tweaked energy management systems with the ISG Package. Hey - our $400 had to go somewhere?
 

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Cerato S Hatch Auto
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1,237 Posts
Yes. I have a long sweeping off ramp and while decelerating it feels like its tugging and deliberately slowing the car down. I wish I could see if its even shifting gears while decelerating.
KIA Cerato auto doesn't change down on deceleration as you describe; obviously, if you come to a halt, it will change back to 1st, but it's a bit hard to see exactly when this happens because the display helpfully displays "D", rather than the actual gear. On the other hand, the Mazda 6 displays the gear number even when you're in "D".

I think I have issues with these auto trannys. Wish my EX had a 6 speed manual.
I think the auto transmissions do a very good job. The Rio is only doing what many "sporty" drivers would do going down a hill; it can't predict that you are going to stop. Could be that the transmission needs a manual switch to select "sporty" or "econo" modes.
 

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12 RIO 5 SX, 07 VW Passat 2.0L turbo 1952 Siata Diana
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All torque converters have a stall speed. When you are going slow enough to have a point lower than the stall speed,the torque converter releases.
 
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