Why ultrasonic cleaning? Isn chemical cleaning just as effective?
Some service facilities do offer chemical and/or “on-car” cleaning methods. Using harsh chemicals to dissolve deposits can damage some injectors immediately and may cause long term damage to oxygen sensors and catalysts. Both GM and Nissan have issued technical bulletins warning technicians against this potentially expensive mistake. Ultrasonic cleaning, according to the Society of Automotive Engineers, is the most effective and safe cleaning method. Why bother with flow testing first; can’t they just be cleaned? Measuring the delivery volume of each injector before it is cleaned and again after cleaning insures uniform distribution of fuel to each cylinder. An average restriction for any given injector, before cleaning, is 8%. This restriction results in a lean mixture at the oxygen sensor. The overall result is a richer mixture for the entire engine, as well as an emissions increase in hydrocarbons by 26%, and carbon monoxide by 16%! This hinders the car’s performance, increases emis
