Walnut Shell Blasting in

Mallard Auto Care is the premier Castro Valley auto repair facility providing cutting edge digital diagnostics, as well as hard-to-find services, including R-1234YF air conditioning system recharge, and walnut shell blasting (aka walnut blasting) for vehicles with GDI engines.

Older direct injection (GDI) engines were designed to provide greater power and improve fuel efficiency at the same time. Unfortunately this design carries one drawback –carbon buildup on the valves. The side effects of the carbon buildup can include hesitation, even check engine light. Fortunately, walnut shell blasting can remove carbon buildup and return a GDI engine to its former glory. Modern GDI engines have been re-designed to avoid carbon buildup, but there are plenty of older Audi, BMW, Volkswagen, Kia and Mazda vehicles that have the original GDI engine design, and can suffer from carbon buildup.

What is Walnut Shell Blasting (aka Walnut Hull Blasting)?

Finely ground/crushed walnut shells provide plenty of abrasive power to remove carbon buildup, yet are softer than sand (no sandblasting) and being silica-free, walnut hulls are considerably more environment-friendly. We use equipment specially designed to clean GDI engine carbon buildup. It provides controlled air pressure that blasts ground walnut shells over (closed) valves, and the walnut shells act as an abrasive that cleans the valves and intake manifold and carries away the carbon buildup.

If you notice decreased performance, hesitation, poor drivability, or if the onboard computer illuminated the check engine light, bring your vehicle to our Castro Valley auto repair shop, and we will diagnose the root cause of the problem – if your vehicle has the older design of the GDI engine, and if carbon buildup on the valves turns out to be the culprit, we can offer walnut shell blasting service – entire procedure, i.e. engine diagnostics and walnut shell blasting can usually be performed the same day.

At Mallard Auto Care we combine cutting-edge technical skills with superior customers service, so when you visit our shop – whether for minor service or major repairs, you can anticipate:

  • Free local Uber or Lyft so you can go about your day
  • 3 year / 36,000 mile nationwide warranty for your peace of mind
  • Original Equipment quality parts
  • In most cases, same day service completion
  • Nationally ASE certified technicians working on your vehicle
  • Discounts for the Military and First Responders

So when your vehicle needs a bit of TLC, bring it to Mallard Auto Care in Castro Valley. We offer full range of automotive maintenance services and repairs. If it does turn out that walnut shell blasting is what your vehicle needs, we will get this completed and get your car back on the road.

For your convenience, we offer online appointments, or you can call us at the shop and we will be happy to answer your questions, and to schedule an appointment at the same time.

Walnut Shell Blasting for GDI Engines in Castro Valley

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