My 04 g35 starts up kind of rough. My friends and I have narrowed it down to what we think is dirty oil lifters. I have been thinking about either taking it to the local nissan dealership for a tune-up or I've also thought about running a bottle of seafoam and letting it cycle through. Anyone ever had bad side effects from using seafoam?

 

Sea foam worked wonders on my car. Recovered 3 MPG. But that only cleans carbon build up. If you have dirty oil lifters you should try putting in rislone, it's made to clean lifters