My 93 is making a strange noise that is intermittent buzzing sound that is coming from the fuel pump (not the in tank pump). My question is, is there anyway i can test the in tank pump to make sure it isnt actually the in tank pump going out making the normal in line pump work twice as hard? the in tank pump is a 40$ fix vs 100+ for the in line

 

In the Tank - 240 Volvo Tank Pump and Sender

 

Thanks!