My 2015 Diesel 1.6, after a rocky start

[Tactical]

Hi there,

My Kia C'eed has had this problem with idling smoothly for years, and I only just noticed it a few weeks ago. At first, I attributed it to the bitterly cold mornings, but now that the mercury is higher, I can't get it to rev up to idle smoothly.
Occasionally, it sounds normal again, but like I mentioned, it's the exception these days; to help it along, I have to rev it up a bit to prevent that rough idling.

One of the sensors on my diagnostic machine read 108C, which is obviously wrong when I start the car from a cold start. Maybe this is the root of the problem. I tried turning off all the visible and accessible sensors to see if their live data would go awry, but none of the three did manage to alter the 108C. "Exhaust gas temperature valve pre particulate filter" is the name of the sensor to which you may be referring. Is this one plugged in but hidden from view?

If you have any suggestions on where I might look for the issue, I would be eternally grateful.

Just so you know, the MAF sensor is one of the most blatantly responsible parts of this. I took it apart to clean it with the right stuff, but it's designed so that we can't get a spray nozzle near it; I prayed it would do the trick, but alas, it didn't.

[Bitxx]

You can find a schematic to help you identify the location on partsouq. Either look at the exhaust before the filter or at the filter for the sensor

[Tactical]

Hello, I appreciate your recommendation. That Partsouq even existed before I knew it. I am impressed by your discovery.

[WannaVulture]

Although I could be completely mistaken, I don't think that sensor has anything to do with cold starting or idle; its intended use is to help with warm engine and DPF regulation.
Located on top of the DPF/EGR valve assembly, next to the DPF sensor hoses, is the larger CRDI (2.2) that I possess.

Rough starting/idle...probably due to...
Shiny Plugs?
Sensor for measuring the temperature of vehicle coolant
Injector leak
Primer bulbs are a typical source of air leaks in fuel feed systems.

[Tactical]

Will turning the plugs on again (I mean, letting them light twice before ignition) do anything? Nothing changed after I tried this. The sound and sensation are constant, and I can't tell that the weather is changing either.

Regarding the coolant temperature sensor, I used the diagnostic program I mentioned before to check all of the sensors' readings; upon cold start, every single one showed the same reading as the outside temperature.

It simply doesn't idle at high enough RPMs; when I mentioned that it felt rough, I didn't mean that it coughed or sputtered. It usually hovers around the 1000 mark. It typically gets by on its own when I press and hold the accelerator for three or four minutes, which brings it up a bit.

I need to restart the tool and collect all the values before I can share them with you.