i have a 98 gmc jimmy 4x4 i recently changed the column fuel pump and head gasket's it gives me a hard time starting everytime it's cold if i shoot a little starting fluid in it it will run until it burn's up the starting fluid it's acting like it got no pressure i hear the pump i also changed the filter inline today and still got the same problem could it be a weak pump what pressure should i have when it's running and warmed up and when i start it