Worked perfectly! My Buick told me error numbers 13 a 34.. So my lambda was dead (so I replaced it) and my MAF sensor doesn't work properly (ordered it and waiting)..
MAF acts weird, one time the service control light is on, sometimes it'* off.. It happens during the ride.. When the light is off, engine goes smoothly.. When it'* off, engine starts to push-pull while running "D" on idle and the idle itself is unstable too..
I'm going to replace MAF, change spark plugs and also their cables.. Thus solving the problem I hope..