Replacing your spark plugs every 30k miles on your 2000-2006 Audi TT is crucial for engine longevity and performance. Ignition coils don’t have a replacement interval, but they typically last over 100k miles. With both the ignition coils and the spark plugs, you don’t need much time to replace them on the MK1 Audi TT as they are quite accessible and easy to change out.