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For the price of sparkplugs it is always worthwhile changing them as part of an intermediate service to keep the engine performing well. In order to do this, you will need an HT lead removal tool. Do not attempt to remove the HT leads with anything else as they are very fragile and will break. You can source the correct tool for anything between £5-£25. This tool is more robust than the smart one but it will not work on one of the leads:

To start the job, you need to remove the rear panel from the car. You may also want to remove the crash bar to give you more access but this isn't necessary.

Start with the lower plugs. These are located here:

Fit your HT lead removal tool and pull. Be careful when you do so as the leads are fragile. Should the tool slip it may cut into the lead. If this happens you will need to replace the leads as well.

Access to the left lead is limited because of the top turbo water pipe. For this, you will need to use the standard smart removal tool... but be careful!

With the leads removed, you can undo all three spark plugs.

With the plugs removed, inspect them for any abnormal combustion. The lower spark plugs are usually a bit dirty. This is perfectly normal:

The standard plugs are NGK LKR8A:

Fit your new plugs:

For the NGKs, tighten these as far as you can by hand. Then use your ratchet to tighten through 180°. You'll feel them tighten as they seal into place. DO NOT OVER-TIGHTEN as you will damage the cylinder head!

Refit the HT leads with the removal tools. Push hard until you hear them click back into place.

Remove the top three HT leads in the same way as for the bottom. Take great care not to snag the leads on the edge of the engine bay when you they come free.

Now turn your attention to the top plugs. Unclip the leads from the fuel rail:

Pull the HT leads off the plugs in the same way as for the lowers. This time, there are no space constraints to consider. Then you remove the leads, check that there is no debris sitting around the spark plug. If there is, use a vacuum cleaner to remove the bits as you don't want these falling into the cylinders.

Now remove the old plugs and replace with new in the same way as for the lower plugs. Ensure the leads are fully home before starting the engine.

Start the car and check that all cylinders sound like they are firing correctly. Refit the rear crash bar and panel.

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