What is the solution for high cylinder pressure reported by EA888?

[DiCollin]

EA888 reported high cylinder pressure solution is to remove the spark plugs and combustion chamber to check for carbon deposits in the combustion chamber. Excessive carbon deposits in the combustion chamber can reduce the cylinder's volume. When the carbon deposits reach a certain thickness, the volume of the combustion chamber will significantly decrease, leading to excessively high cylinder pressure. Below is relevant information about the cylinder: 1. Introduction: A cylindrical metal component that guides the piston in linear reciprocating motion within the cylinder. Air in the engine cylinder converts thermal energy into mechanical energy through expansion, while gas in the compressor cylinder is compressed by the piston to increase pressure. 2. Cylinder types: Cylinders can be integral or single-cast. Single-cast cylinders are further divided into dry and wet types. When the cylinder and cylinder block are cast as one piece, it is called an integral cylinder. When the cylinder and cylinder block are cast separately, the single-cast cylinder liner is called a cylinder sleeve.

[AndresMarie]

Last time my own EA888 also had high cylinder pressure, and it took me a while to figure it out. The main thing is to check for carbon buildup, especially on the back of the valves. Severe carbon deposits in direct injection engines can hold the valves open, causing abnormal compression ratios. You can try walnut blasting to clean the intake ports first—it’s quite effective. Then check if the piston rings are stuck, causing blow-by. Here’s a simple method: after the engine is warm, remove the oil cap. If there’s noticeable airflow, the rings might be faulty. Don’t overfill the oil—exceeding the upper limit can also cause abnormal cylinder pressure. Using spark plugs with the wrong heat range or worn-out ones can affect cylinder pressure readings too. Oh, and it’s best to first connect a diagnostic tool to check if the pressure values across all cylinders are even, to rule out sensor errors.