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hey all,

Is anyone wondering as to why their ICE is running sometimes? i often will just tap the brake to remind the car that i am going downhill and haven't touched the gas in a minute, so we can do without the engine.

this isn't during the initial start up mile or so, and it's with all climate control off. maybe there's a reason i don't know as to why it needs the ice? but for now, i tap the brake it gets the message and cuts the engine so i can coast for free.

it's not a big hardship, just don't like confusing the people behind me. would be nice to have different program modes.
 

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My suspician is that the ICE should have been running at that point. You may have over ridden it. You did the right thing if you don't trust KIA's programming. However, contrary to conventional logic, it may well be that the ICE running in that situation is best for max economy. The engine often runs just to charge the battery even when not needed otherwise.

Nothing more than a guess.
 

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I took a bit of a waste trip on the highway as the store was closed when i got there, but that is a different story. On the way back I found the engine on my KIA likes to do some strange decisions. The highway has a section that goes through a small valley. I am driving at around 110kph/70mph and the engine is ticking over at about the 5.4L/100km .. and you can tell it's in top gear from the sound. I go down a hill and the engine turns off and switches into EV mode. All is good. on the flat bit after the decline, the engine turns back on and in top gear running again at 5.4L/100km. Then on going back up the hill on the other side the engine still stays in top gear and allowing it to scrub off a bit of speed to say 100kph stays at the 5.4L/100. but when I get to the top of the hill and the road levels off (so you are no longer going up a hill) the engine then decided to drop a gear, jumps to 10~11L/100km, and will stay locked in way until you press down on the gas to bring the speed of the car up to say 115kpg then take your foot totally off the gas allowing the car to go into regen mode for 4-5 seconds, then the car will run normally and allow itself to go back into top gear and the engine fuel usage drops back to the 5.4L/100km. Otherwise, it will just stay in a dropped gear state.



It only does this if you go down into a valley, so down one hill, then shortly back up the other side. If you go up a hill without going down one first, it seems to work fine. I just don't understand the logic in the processor. Now I have only had the car for 4 months now, so it might be a winter temp thing? I don't know until I get to summer and it also hasn't had its first oil change so who knows if something setup wise is still amiss.
 

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I took a bit of a waste trip on the highway as the store was closed when i got there, but that is a different story. On the way back I found the engine on my KIA likes to do some strange decisions. The highway has a section that goes through a small valley. I am driving at around 110kph/70mph and the engine is ticking over at about the 5.4L/100km .. and you can tell it's in top gear from the sound. I go down a hill and the engine turns off and switches into EV mode. All is good. on the flat bit after the decline, the engine turns back on and in top gear running again at 5.4L/100km. Then on going back up the hill on the other side the engine still stays in top gear and allowing it to scrub off a bit of speed to say 100kph stays at the 5.4L/100. but when I get to the top of the hill and the road levels off (so you are no longer going up a hill) the engine then decided to drop a gear, jumps to 10~11L/100km, and will stay locked in way until you press down on the gas to bring the speed of the car up to say 115kpg then take your foot totally off the gas allowing the car to go into regen mode for 4-5 seconds, then the car will run normally and allow itself to go back into top gear and the engine fuel usage drops back to the 5.4L/100km. Otherwise, it will just stay in a dropped gear state.



It only does this if you go down into a valley, so down one hill, then shortly back up the other side. If you go up a hill without going down one first, it seems to work fine. I just don't understand the logic in the processor. Now I have only had the car for 4 months now, so it might be a winter temp thing? I don't know until I get to summer and it also hasn't had its first oil change so who knows if something setup wise is still amiss.

Can't say for sure but yes COLD weather changes the hybrid performance experience entirely. In Spring, Summer and Fall I've been on a 65MPH interstate, going 65, on FLAT terrain, and had the car alternate several times between EV only, engine only, and Hybrid mode. EV only at those speeds is infrequent and doesn't last long. I suspect that many on here are NOT using their "head unit" screen, i.e. "the radio" and observing their status there. On the dash borad behind the steering wheel, there is NO indicator for HYBRID mode but it DOES show up on the large touch screen head unit in a sub screen/menu of the Hybrid menu. There, as you drive you can see LIVE changing from EV, to Hybrid (engine AND EV battery), IDLE, and Engine mode.........interesting screen.
 

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It only does this if you go down into a valley, so down one hill, then shortly back up the other side. If you go up a hill without going down one first, it seems to work fine. I just don't understand the logic in the processor. Now I have only had the car for 4 months now, so it might be a winter temp thing? I don't know until I get to summer and it also hasn't had its first oil change so who knows if something setup wise is still amiss.
I see the same behavior in mine sometimes, but I think it's really just an artifact of the particular driving conditions. The ECU seems pretty reluctant to drop a gear when going up a hill (even with the cruise control on, so it's not just me) and sometimes I get to the top at the same time it finally decides to shift down. This leads the the behavior you describe. You are now on level ground with the ICE running and it takes some time for the ECU to decide to shift up again. As you noted, you can force it to shift up or shut the ICE off entirely by taking your foot off the gas for a second. With the cruise on it takes a few seconds for the ECU to recognize that the car is no longer going uphill so the ICE stays on in a lower gear for a bit longer.

Not sure it's a problem, just a quirk of programming that shows up in certain conditions. The ECU's logic is pretty limited as are its sensors so its knowledge of the environment is a bit unclear so you can get behaviors like this sometimes.

One thing that's obvious is that cars would benefit greatly from the ability to sense what's coming rather than simply reacting to what's happening now. In the situation we're talking about, if the car knew how long the hill was and how steep it could make better decisions on how to climb it most efficiently. Giving the ECU that capability would take a LOT of additional sensors and processing power, probably not worth it for a car like the Niro.
 

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Can't say for sure but yes COLD weather changes the hybrid performance experience entirely. In Spring, Summer and Fall I've been on a 65MPH interstate, going 65, on FLAT terrain, and had the car alternate several times between EV only, engine only, and Hybrid mode. EV only at those speeds is infrequent and doesn't last long. I suspect that many on here are NOT using their "head unit" screen, i.e. "the radio" and observing their status there. On the dash board behind the steering wheel, there is NO indicator for HYBRID mode but it DOES show up on the large touch screen head unit in a sub screen/menu of the Hybrid menu. There, as you drive you can see LIVE changing from EV, to Hybrid (engine AND EV battery), IDLE, and Engine mode.........interesting screen.
Actually, my screen does. On the left side of the screen, there is an indicator that you are in EV mode. As well, if you are on the main screen, when the ICE turns off, the Fuel Economy bar drops to zero. I find that an easier way than having to swap the side screen and it takes me far longer to look at the middle console than just a quick glance downwards to the screen behind the steering wheel.
 

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Have you checked the battery charge indicator? I suspect that going up the hill you depleted the battery since it may have been using both ICE and Electric motor to get up the hill, so then even though you were at top and going down, the ICE needed to run to recharge the battery.
 

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Have you checked the battery charge indicator? I suspect that going up the hill you depleted the battery since it may have been using both ICE and Electric motor to get up the hill, so then even though you were at top and going down, the ICE needed to run to recharge the battery.

not sure if that was directed at me. In my case with the engine dropping a gear at the top of hills. I do keep my eye on the battery level. I have had the car keep the engine running even with there being 3-4 bars on the engine warmth screen, and the battery towards the upper part of the full spectrum. So I have concluded that I don't understand the logic inside and am probably missing something that would trigger the engine to keep running when it doens't really need to. But likewise, I have had times when I felt sure that the engine would kick in as the battery is down below the 1/2 way mark on the HEV scale but I guess I was driving at just the right speed and perhaps down an unrealized incline that the EV mode has clicked in and stayed running.


What I sometimes wonder is the engine fuel economy bar, how accurate is that. I have been sure that it has been running around the the 7-9L/100km level for most of a trip when driving, but when I have turned off the car, you get it's estimation of the fuel economy for the trip and have been given a much lower number like 5.4L/100km. It is not half but substantially enough below what the bar line has been showing that it brings into question what is accurate or not.
 
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