hello, when i broke my car in with the static break-in i did two HALF tanks accidental (did'nt read instructions) well now i have done 2 half tanks at low speeds and 2 full tanks at low speeds. i have one more full tank left to go before i can reach full speed. My question is that it has a ruff sound. I know it says it will have a ruff sound but fr how long? maybe i'm just over worrying but i did only do 2 half tanks of static break in ... will this affect my cars performance hugely? any views will be most helpful. I just hope that the ruff sound won't be there to stay [&o]