RTMG Universal Carbon Fiber Oil Catch Can - SmallOne common problem of the TSI engines is the carbon build up on the intake valves. Due to the direct injection fueling system, where fuel is sprayed directly into the combustion chamber, the intake valves are not cleaned by fuel, therefore carbon deposits, a product of oil fumes of the stock PCV system, build up on the valves. The RTMG Carbon Oil Catch Can can reduce the carbon build up on the intake valves up to 60%. The catch can also prevents oil