Beware! Spark Plug Quality Issue in recent Years!
Recently the market has been flooded with low quality spark plugs which look very identical to the factory ones. However, they are very different with respect to their performances and reliability.
Although they are iridium plugs which are supposed to last as long as 10,000 km, some have turned out to be defective even just after installation.
Common issues that occur are the tip wearing off fast and combustion gas leaking around the ceramic insulator. This has caused much undesired issues both to the repair shops and car owners. Moreover, these plugs are in the original packing and can even escape the eyes of trained technicians. The quality can only be discovered after being installed into the working engine.
Take a close look at the tip of the ceramic insulator, which show that bad combustion gas has leaked from the ceramic insulator and that the iridium tip has worn out quickly causing a big gap, which results in misfiring and bad acceleration.