May be dump a can of injector cleaner in the gas tank.
Your you sure you don't have a vaccum leak, check all the lines.
178,000+ miles, 5/20/12 new ej257 short block, 8/20/11 installed VF52 turbo, @20.8psi, 280whp, 300ftlbs. CHECK your oil, these cars use it.
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