How can I troubleshoot a faulty ignition coil in my Vauxhall Astra?

I've noticed that my Vauxhall Astra is experiencing a rough idle and occasional misfires. I suspect that the ignition coil may be causing these issues. What steps should I take to diagnose and resolve this problem?

First, try to visually inspect the ignition coil for any signs of damage or wear. If it looks normal, you can then use a multimeter to check the resistance of the coil. If the resistance is outside of the specified range, it may be time to replace the ignition coil.

Another way to troubleshoot a faulty ignition coil is to swap it with another known working coil in the same engine. If the issue persists, then you know that the ignition coil is not the problem and you can focus on other potential causes.

If all else fails, it may be best to bring your Vauxhall Astra to a trusted mechanic for further diagnostics and repairs. Ignition coils are a vital component of your engine and it's important to address any issues with them as soon as possible.