while i am driving, my engine hickups and at the same time my main relay is making a clicking noise. it does this randomly. there is nothing i can do to make it do this. i already know that the main relay controls the power for the ecu, fuel pump, and injectors. so my quesion is, what would make the main relay do this? -i have already got a manual and followed the procedures for checking the main relay and it works fine. -i have already got another pr3 ecu that i know works fine and it still does the same thing. ?could a bad fuel pump cause this? ?could a bad ignition switch do this? any help or a point in a direction would be greatly appreciated.