Hi there! At the moment, my 2013 Clio's D4F-722 engine is giving me trouble. Even after multiple investigations, the problem remains unresolved.
Then, what exactly is wrong? Just as the engine is getting hot, misfiring will begin abruptly. Aside from the misfire event's recorded DTCs, the MIL begins flashing and the wrench and ESP symbols light up. If you rev the engine past 2500 rpm, it will run smoothly again and the MIL light will not flash. Be aware that the engine starts misfiring the second the revolutions per minute (rpm) drop below 2500 rpm, but gains power instantly at that point.
How the car won't misfire "logically" is another strange thing. It might begin misfiring as soon as it warms up, or it could start 30 kilometres later. When the engine is misfiring, you can fix it for X amount of time by turning it off and then back on again.
What other people have done or substituted:
Array of coils
End caps
Measurement of crank position
Resistance measurement of plug leads
My accomplishments:
Valve adjusting
Gaskets that cover valves
Gaskets used on intake manifolds
As it begins to malfunction, there are a few DTCs that can be recorded:
Misfire in Cyl 1
Problem with Cyl 3
Found a misfire while fuel levels are low
Fumes from pollutants
Occasionally, while driving normally, you might hear a "Pollutant misfire" or "Cyl 1 or 3 misfire" even though the MIL isn't flashing or the engine isn't running rough.
It seems to reason that we should start searching for an electrical component since the RPMs have such a significant impact on the misfires. After the engine has cooled down tomorrow, I will check the valve clearances again.
This is just a brainstorming session, so please accept my apologies in advance if the post is badly worded.