triangle12

Going to change spark plugs but wanted opinions on if I should change all coils too? No engine lights or issues other than a rough idle. It's an 07 E63 with 105k miles. Thanks.

chassis

I don’t see any harm, in fact it could help. Coils in my view are a replace-eventually item. 100k miles seems as good a point to replace, as any. They are passive devices and don’t require coding/programming which makes replacement easier.

triangle12

Thx. Guess I should change them since I have no idea if it's ever been done. Just didn't know typical life span of coils and they are $40+ each. At least I only have 8 plugs to replace instead of 16 like the C55 I used to own . Thanks again