This Preliminary Information communication provides information to the technician about vehicles that may have a buzz noise at idle after fuel pressure regulator replacement. Technician will need to gain access to the fuel pump. After gaining access to the fuel pump check the power and ground for voltage drop with the key in the off from the fuel pump to the battery post. Technician should also check the pin fit and terminal drag. Technician may replace the fuel pump connector with the updated part using the latest version service bulletin 04-06-04-088C. Technician should inspect voltage drop points at the UBEC, fuel pump relay, ground at the frame and the battery cable grounds. If excessive resistance is found at the crimps, replace the crimp n seal splice sleeves for the affected circuits. If the circuits do not have high resistance replace the regulator using part number 19236428.
