Presence of oil in the combustion chamber.

[IrvesBMW]

Greetings, I own a BMW 116i, which is a model from 2012 and belongs to the F21 series. An really troublesome automobile. I have successfully resolved the majority of my oil leaks and have seen positive outcomes. Subsequently, there was a misfire detected in cylinder 4. Replaced the spark plugs and coils, however the issue persists in the same cylinder. Disassembled the manifold and saw an accumulation of oil in the combustion chamber of cylinder 4.

It is worth mentioning that I saw the presence of oil on the spark plug, both on its surface and around the threads. It seems that the gasket on my valve rocket cover broke, causing a leak into the spark plug.
The spark plug was found to be loosely attached and had oil accumulation at the tip, with visible oil present in the surrounding hole. Could the presence of oil in the combustion chamber be solely attributed to oil leakage from the spark plug?

I want to do a compression test. I hope that the issue does not include a damaged seal inside the combustion chamber, since I would then have to repair it myself. I have no prior experience in fixing a combustion chamber, which makes me apprehensive about doing so. While I understand that the test will assist me in determining the issue, is it conceivable that the spark plug just facilitated the leakage?

Regarding compression testing, I have seen that some automobiles allow for the removal of the fuel line fuse and ignition fuse to facilitate the test. Does this car possess these specific fuses, or are there other processes that need to be followed?

Appreciation is extended for your kind gesture.

[ChatMaven]

Indeed, it is feasible; nevertheless, the compression test will ascertain its validity.

[ChatMaven]

I would remove the fuse for the fuel pump.

[IrvesBMW]

Gratitude is expressed towards @ChatMaven. In order to confirm an alternative hypothesis, would the presence of a seal problem not result in the depletion of oil from the combustion chamber? Based on my assumption, does the oil go in a downward direction? Unless there is a problem with the seal being broken around the top.

[ChatMaven]

The source of the issue seems to be a post-combustion oil leak, which might be caused by a faulty head gasket, a loose plug, or worn valve guides. However, if the problem were with the valves, you would have likely seen smoke at engine startup.

[VWDaveBMW]

I would want to replace the plugs. whether the oil seems greasy when the plug is removed, it is likely that the oil level has decreased. It would be prudent to determine the actual cause before replacing the rocker gasket, since it would need to be removed regardless whether the head is taken off.
Replace the injector with a different cylinder and observe whether the problem transfers to the new location.
Performing a compression test is a recommended course of action.

[IrvesBMW]

Yes, I am considering replacing one of the fuel injectors with another. I often notice the smell of gasoline, and it has been more pronounced recently. However, upon discovering a buildup of oil in the chamber, I am contemplating doing a compression test after removing the oil residue.