PDF associated: /PT 50-0004.pdf

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JDA5244 PT 50 0004 Rich Running Fuel Injected Engine Causes Booster Failure All vehicles with gasoline fuel injected engines and vacuum boosters Booster failure due to ruptured diaphragm hard pedal no assist A rich running engine due to improper fuel management causes excess gas or gasoline fumes to enter booster thus destroying the diaphragm Ensure proper operation of fuel management system Check for defective injectors high fuel pressure leaking fuel pressure regulator and proper ECM operation Check the old booster for gasoline odor If it smells like gas DO NOT install the replacement unit until the problem is corrected Typical vacuum booster diaphragm failure due to gas or gasoline fumes Another cause of diaphragm failure is master cylinder brake fluid entering the booster due to a faulty intermediate pushrod seal in the booster If brake fluid is found between master cylinder and booster the booster will have to be replaced see ProTech PT 50 0001 Application Problem Cause Solution Note