yeah I could hear mine working too- trouble is the signal wasn't enriching the fuel, therefore i heard it working i just never felt it. the turbo's surge can be felt at around 2000 rpm- it's a boost in power. checking it out is easy and doesn't cost anything. your prefilter should show only clear golden diesel fuel with no air bubbles. if it's black and it's always been that way you could have a chronic fungus issue.

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'02 BMW 325i
'85 300D 450k
'93 190E 2.6 170k(killed by tree)
'08 Ducati Hypermotard 1100S 6k
'06 Ducati S2R800 14k(sold)