A mechanic sprays a foam or special cleaning solution into the intake manifold. This is to remove the carbon deposits on the valves and pistons in engines with high mileage and direct fuel injection. The service may be beneficial in those engines, but no manufacturer at this time includes it in their recommended maintenance.
If your car is running fine, and you are getting good gas mileage, you won’t notice much improvement from this service. Check with one of our mechanics at Tire Works if you are unsure about adding a fuel induction service for your car.