Stop using Mobil 1.
Shell Rotella t6 5w-40 or Castrol Synthet,
I've gone to using Amsoil European 5w-40.
I've been using the same K&N kit I bought back in 2005.
201,000miles 5/2012 ej257 short block, 8/2011 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
Engine Build - Click Here