For more than 16 years, N.W Sand & Gravel has provided professional and quality service to Snohomish and King Counties. Since we produce our own topsoil and compost, we pass those savings on to you. We have the systems and capability to diagnose problems through your truck's computer or ECM (electronic control module). If your check engine light is on, we can diagnose what faults are happening, from misfiring cylinders to EGR system problems and beyond.