BMW's direct-injection engines improve performance and save fuel, but at a price. Direct injected engines are able to yield more power when compared to engines of similar displacement. This design means that the fuel is injected directly into the combustion chamber of each cylinder. The fuel injectors are no longer placed before the intake valve, but instead are placed directly in the cylinder itself. The result is more complete combustion and cooler cylinder temperatures that allow for a higher compression ratio for an approximate 15% gain in fuel economy, while increasing torque as much as 50%. This is part of what has made the N54 and N55 platforms so great in regards to reaching amazing horsepower levels.
The downside to this is that the regular cleaning of the intake valves from fuel exposure no longer occurs. The intake valves are now only in contact with air and blow-by gases from the crankcase breathing circuit. This results in deposits of carbonized fuel and oil in the intake tract as well as on the intake valves themselves. Over time heavy buildup of carbon deposit on the valves can prohibit them from closing properly, and can result in a rough idle, reduced throttle response, and increased oil consumption.
Your N54/N55's engine intake system needs to be cleaned regularly to perform at its peak. The dealership, along with other experts (such as Burger Motorsport, Pure Turbo, Dinan, and Cobb) recommends you clean the valves every 30,000-40, 000 miles. The use of fuel additives has shown to have no effect on the buildup, since the fuel does not come into contact with the intake tract or the valves. Methanol injected setups, at times, can potentially slow down the process, but have also shown to have very little impact on keeping the valves clean. This leaves walnut blasting as the most efficient and effective alternative to cleaning. The Genuine BMW blasting tool uses pressurized air to inject fine walnut shell granules into the intake tract. The walnut shells hits the carbon at high speed to remove all the buildup in its entirety, without causing any damage to the cylinder head, walls, or valves. Our blaster is equipped with a vacuum adapter that's designed to catch the used media and deposits, leaving your engine bay clean, and free from media debris.
We are running a special on this service for the next few weeks, and are currently taking appointments. Introductory price will be set at $375. We are currently having a group buy, which can result in even lower prices (depending on how many appointments we fill in the upcoming weeks). Call us at 210.232.1507 to claim your spot.