2004 Yukon,5.3 flexfuel. Last July at 100k,miles fuel pump got noisy. Replaced with Delphi pump,new fuel filter. Things are good for 8 months. Last month we had a really cold week,single digit temps briefly. After that,the pump got noisy again,only 4k miles since replaced. Got a new pump,warranty,replaced it and filter again,new pump is noisy right off the bat. Replaced flex sensor,looking for a restriction,no difference. Have now put the old 4k mile pump back on,as it is a little less noisy than the new one. It seems like I have a restriction causing this noise?? Also,would the pressure regulator on the manifold cause a restriction?? Car runs great. Help.
Thanks.
Thanks.