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I own a 2013 hardtop vehicle with a basic model equipped with a N16 engine. After removing the valve cover to get an image of the timing chain, I reassembled everything. However, the engine began to operate in a very unstable manner around 10 seconds later and eventually ceased functioning. I made another attempt, but it resulted in the same outcome. The generated code is 2B5C. In addition, it began to exhibit misfires across all cylinders.

This automobile performed very well before this incident. The code indicates a problem with the Mass Air Flow, however, I have come across suggestions from others stating that the throttle body has to be replaced.

We really value any guidance or recommendations.

Thank you much!

Have you verified that you did not inadvertently manipulate the wire harness when removing the valve cover?
Occasionally, a new issue may arise just by chance while carrying out other tasks. It is possible that it failed coincidentally when you removed the lid.

Although I have no personal experience with it, I conducted an online search and discovered that the throttle body is often identified as the underlying issue for this particular code. There have been many theories suggesting that the plastic gears responsible for operating the throttle blade wear down and become imprecise, potentially allowing excessive air to enter the engine. This may trigger the mass air code. Essentially, the ECM (Engine Control Module) requests a certain throttle setting. However, in some cases, the ECM goes over the requested setting, causing the mass air code to be triggered. This occurs because the mass air sensor detects a greater amount of air than what the ECM initially requested.

Understood, but, my knowledge of the subject is only based on a cursory internet search. However, it is advisable to investigate more.

Inspect the ground wire located in the centre of the rocker cover bolts, which should have an 8mm nut attached to it. Additionally, ensure that the PCV pipe is not damaged, as this might potentially impact the intake air mass detected by the MAF.

While it is true that a damaged PCV (Positive Crankcase Ventilation) pipe might cause the air-fuel mixture to become leaner, it is important to note that the PCV connection is located downstream from the mass sensor. This means that if the PCV pipe is broken, the sensor will not detect any more air entering the manifold.

Indeed, as it is a N16 model, it is equipped with a standard Mass Air Flow (MAF) sensor. The previous N12 model also featured a MAF sensor installed in the intake manifold.

Understood.