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Sorento SX 2013
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Discussion Starter #1
a couple of days ago i was going bumper to bumper regular city traffic, and just when i hit the break and shifted to neutral the engine turned off, in fact everything went off, but luckily the electrical came back quickly, and i was able to stop on time.

no idea what the hell happened, but after restarting the car, everything worked fine again.

my guess, it's probably a weird sensor glitch

I've always been shifting to neutral to coast the rest of the way up to the light or bumper in front or me, never had that happen before.

I'll take it to the dealer to have it checked out, but they'll probably say it's nothing.

It have not happened since then.

Has anyone experience something like this before? :confused:
 

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2013 Sorento EX V6 AWD
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a couple of days ago i was going bumper to bumper regular city traffic, and just when i hit the break and shifted to neutral the engine turned off, in fact everything went off, but luckily the electrical came back quickly, and i was able to stop on time.

no idea what the hell happened, but after restarting the car, everything worked fine again.

my guess, it's probably a weird sensor glitch

I've always been shifting to neutral to coast the rest of the way up to the light or bumper in front or me, never had that happen before.

I'll take it to the dealer to have it checked out, but they'll probably say it's nothing.

It have not happened since then.

Has anyone experience something like this before? :confused:
Just curious...why would you do that? What's the perceived benefit of shifting to neutral while rolling up on a light?

Best,
 

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2012 Sorento EX V6 AWD w/Sunroof, RIDES a 2012 Suzuki GSXR 600
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Agree... no point in shifting, harder on the tranny. Just take your foot off and coast.
 

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Sorento SX 2013
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237 Posts
Discussion Starter #4 (Edited)
in neutral it rolls just as expected by the laws of physics

if i just coast with the tranny engaged it eats away the free roll, even when you leave it on 5, it'll auto down shift to 5 & 4 most of the time when there's not enough speed to keep it on 6

it's an habit i picked up from previous cars, it breaks faster in shorter distance for sudden stops

with the tranny engaged you are still being pushed forward a short distance even when you floor the breaks in a sudden stop manoeuvre

either way, the point is the engine suddenly shutdown by itself, which i find extremely weird.

never had this problem before on other cars, by shifting to neutral and stopping suddenly, well not even on the Sorento until just over the weekend.

I've been driving the same since the day i picked it up from the dealer without any issue until last weekend.
 

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2008 SpectraSX, 2014 Optima LX,2006 Jeep Liberty, Linux Mint Mate
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BB6886..
You sound like a technician when you said "Engine went off-line by itself".
I think you may have found a programming "glitch/bug"...

Todays cars "fly by wire" meaning we as drivers "request" something to happen (accelerate/push to start/roll up a window/set the alarm) the ECM/TCM/BCM modules (hopefully) perform the task we requested..

I think you may have found an error in the ECM/TCM program that would not have "normally" been found.. Your sequence of "events" probably have not been taken into account when the code was written..
-let up on the accelerator (computer controlled)
-applied brake (computer monitored)
-placed range selector in neutral (computer monitored)
-engine RPM drop to "idle" (computer controlled)
THEN the ECM/TCM "thought" you were going to shut down the engine and performed that task...

Even "if" it doesn't create an unsafe condition and you can "recover" by restarting/rebooting the ECM/TCM... It's unnerving to say the least..

I WOULD contact both your dealer and KIA Corporate about a possible programing error so they can locate the "possible" bug and correct the code. You might want to cut and paste what I posted here and add/correct any sequence of events you may wish to add... You will help KIA and other Sorento drivers by doing so...
Don't take a brush off from your dealer if it happens...Contact KIA Corporate.
Dave
 

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Sorento SX 2013
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Discussion Starter #6
Thanks Dave,

Yes, that's definitely the plan, and thanks for the troubleshooting steps :D I do believe this would actually make it more understandable to the service people at the Kia Dealer

However the actions taken were as follow:

-let up on the accelerator (computer controlled)
-placed range selector in neutral (computer monitored)
-applied brake full force (computer monitored)
-engine RPM drop to "idle" (computer controlled)
THEN the ECM/TCM "thought" you were going to shut down the engine and performed that task...


the above sequence of action has been working great except for that single incident.

doing this sequence in reverse, can cause damage to the tranny if you over shift into Reverse
-applied brake full force (computer monitored)
-placed range selector in neutral (computer monitored)

i've actually tried this a couple of times on the Sorento, it wouldn't even let me do it, there seems to be a build in safety that prevents you from shifting to Neutral if you are already breaking

However switching first to neutral for the free roll, then hitting the brakes, is an allowed move according to the ECM/TCM programming
 

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2012 Sorento EX V6 AWD w/Sunroof, RIDES a 2012 Suzuki GSXR 600
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Or you could just leave it in drive and not worry about it.
Actually I remember reading in the manual that you should always have it in drive when moving ie, coasting downhill (or to a stop) . They did not recommend otherwise.
 

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2013 Kia Sorento EX V6
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Or you could just leave it in drive and not worry about it.
Actually I remember reading in the manual that you should always have it in drive when moving ie, coasting downhill (or to a stop) . They did not recommend otherwise.

I read the exact same thing while reading the manual of my 2013 which I just trade in my 2004 for a 2013 EX V6...some of you may remember me :p

It stated it creates an unsafe environment or something of that nature which makes sense. It would create a premature wear on the transmission also.
 

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2012 Sorento SX, 2011 Sportage EX
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Coasting in neutral is also going to add brake wear. A big part of what slows the car are the gears, might end up replacing brake pads sooner.
 

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When I read 'bumper to bumper traffic', I'm thinking of stop/start traffic jam style... in which case... I also shift to neutral. Less wear on the brakes, less fuel consumption (engine fighting extra load due to trans. being engaged, etc)

If on highway or road and doing a decent speed (10km/h+), then leaving it in gear is better fuel consumption.
When the vehicles kinetic energy turns the engine, the engine uses no fuel.
 

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2012 Sorento SX AWD Titanium
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I just want to add that this has happened to me in my Sorento as well. Yesterday in fact. I decided to "coast" on an off-ramp that eventually ends at a red light. I was going around 60 mph, no traffic to contend with so I put it in neutral. I can't remember for sure but I may have been lightly braking when I shifted into neutral or I may have braked lightly right after shifting into neutral (I was reducing my velocity from highway speeds). I had the music up and I didn't notice that the vehicle shut off until I realized I no longer had assisted steering or braking, looked down and all the warning lights were on, just like you were in the pre-start ignition phase. I hit the hazards and maneuvered the vehicle to the shoulder so I could restart the engine.
 

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Sorento SX 2013
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Discussion Starter #12
i was able to reproduce it once more, over the weekend, it only comes off when i tried to stop at a red light by coasting to it on neutral then hit the breaks

and this time i did it calmly, did not step on it hard
the gas tank was fully loaded
last time my tank was nearly empty, and the Dealer said "oh it's probably it was low in gas, blah blah blah...."

so, now i know for certain it's not a gas issue, as the tank was full
need to book another appointment with the dealer again to have it looked at
 

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Discussion Starter #13
When I read 'bumper to bumper traffic', I'm thinking of stop/start traffic jam style... in which case... I also shift to neutral. Less wear on the brakes, less fuel consumption (engine fighting extra load due to trans. being engaged, etc)

If on highway or road and doing a decent speed (10km/h+), then leaving it in gear is better fuel consumption.
When the vehicles kinetic energy turns the engine, the engine uses no fuel.
that's exactly correct, use the inertia in your favour
 

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2015 Kia Sorento SX Regency Red, 2012 Kia Sorento SX, 2011 Toyota Hiace
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So there's three owners experiencing this, but not me.

I always do that crusing-downhill-in-neutral evey night when im driving home from work and that never occured to me.

Speed is always 80kph (speed limit) and everything's perfect.
One of my friend even told me it's straining the tranny coz he said if i came from N then shifted back to D, my gears will restart from 1 till 6 again, but when I tried it displays 6th gear in my gear indicator.
 

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2011 Kia Sorento EX V6 AWD & 2010 Hyundai Sonata SE
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So there's three owners experiencing this, but not me.

I always do that crusing-downhill-in-neutral evey night when im driving home from work and that never occured to me.

Speed is always 80kph (speed limit) and everything's perfect.
One of my friend even told me it's straining the tranny coz he said if i came from N then shifted back to D, my gears will restart from 1 till 6 again, but when I tried it displays 6th gear in my gear indicator.
No, it won't strain your gears. These cars are very technologically advanced nowadays so it knows what gear to be in at all times.

Why do you put your car in neutral when going downhill? When you let off the accelerator, your fuel injectors turn off. So when your coasting downhill, you aren't using any gas! Same thing goes for when you are coming to a stop. Your injectors stay turned off until you slow down to a certain speed.

When you put it in neutral, you are idling...using gas!
 

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No, it won't strain your gears. These cars are very technologically advanced nowadays so it knows what gear to be in at all times.

Why do you put your car in neutral when going downhill? When you let off the accelerator, your fuel injectors turn off. So when your coasting downhill, you aren't using any gas! Same thing goes for when you are coming to a stop. Your injectors stay turned off until you slow down to a certain speed.

When you put it in neutral, you are idling...using gas!
Umm...your injectors definitely do not turn off, otherwise the engine would stall every time you released the throttle.
 

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2011 Kia Sorento EX V6 AWD & 2010 Hyundai Sonata SE
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Umm...your injectors definitely do not turn off, otherwise the engine would stall every time you released the throttle.

Your wheels are rotating. Wheels are connected to the transmission and your transmission is connected to your engine. Your wheels will keep your engine turning while coasting. Think of it like a manual transmission. You can pop the clutch with no key in the ignition and the engine will turn over. I can't find a good way of explaining it.

Basically ever modern car has a 'Fuel cut off'. The injectors are controlled by the computer which receives various signals from various sensors. One main sensor being a Throttle Position Sensor.

If you reset your average MPG reading and go down a long hill, you will notice that you will get a really High reading. This is because it recognizes that you are using next to no fuel. Once you start to drive regularly, that number will drop because you are using gas again.

These will help you understand it better

http://www.popularmechanics.com/cars/alternative-fuel/news/coasting-in-neutral-fuel-economy

do automatics shut off the injectors when coasting? - AnandTech Forums
 

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2015 Kia Sorento SX Regency Red, 2012 Kia Sorento SX, 2011 Toyota Hiace
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Nice read! I will probably discontinue my habit which turned out to be more gas guzzler than gas-saver.
 

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2011 Sorento V6 AWD
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No, it won't strain your gears. These cars are very technologically advanced nowadays so it knows what gear to be in at all times.

Why do you put your car in neutral when going downhill? When you let off the accelerator, your fuel injectors turn off. So when your coasting downhill, you aren't using any gas! Same thing goes for when you are coming to a stop. Your injectors stay turned off until you slow down to a certain speed.

When you put it in neutral, you are idling...using gas!
Wow thats a good one, i had to re read that because I couldnt believe someone wrote that. That is not even anywhere close to how it works. The only time your FI is off is when the engine is off, when the engine is on you are always using gas. Shifting to N would save such little fuel that the extra effort, wear to brakes and tranny, and possible safety risk make it not worth while. These are computer controlled cars not old school manual tranny cars, and you cant drive them as such. The manual does state that you should leave it in drive.
 
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