What are the common causes of excessive oil consumption in Vauxhall Insignia?

I have been experiencing a significant decrease in the oil level of my Vauxhall Insignia. What could be the possible reasons for this and how can I fix it?

One of the main causes of excessive oil consumption in Vauxhall Insignia is worn out piston rings. This can lead to oil leaking into the combustion chamber and burning along with the fuel, resulting in a decrease in oil level. It is advisable to get your piston rings checked and replaced if necessary.

Another common reason for excessive oil consumption is a faulty PCV (Positive Crankcase Ventilation) valve. This valve helps in reducing pressure build-up in the engine and prevents oil from escaping into the combustion chamber. If it is not functioning properly, it can lead to oil leakage and consumption. It is recommended to get your PCV valve checked and replaced if needed.

A clogged or dirty air filter can also contribute to excessive oil consumption in Vauxhall Insignia. A dirty air filter can restrict air flow to the engine, causing it to work harder and use up more oil. Cleaning or replacing the air filter regularly can help prevent this issue.

Lastly, using low-quality or the wrong type of oil can also lead to excessive oil consumption. It is important to use the recommended oil grade for your Vauxhall Insignia and to regularly change the oil as per the manufacturer's guidelines.