You may need to remove the undertray
Undo the fixings - use a 10mm socket for this
Don't forget to place a suitably sized receiving tray beneath
Using an 8mm Allen key, carefully remove the sump plug and fully drain the oil. When the sump has emptied, wipe clean the sump plug area with a paper towel and fit a new sump plug and washer. Do not over tighten. Replace the undertray
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