Fuel pump hum
#1
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for the first time, I can now hear my fuel pump hum. Not real loud, like they do when you are low on gas, but a low level hum. Does this mean it is about to die? I haven't noticed it before.
#2
Three Wheelin'
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When did you last check your internal pump it could be that a piece of the rubber hose found it's way to the external pump.
You can inspect the internal pump and after you remove the external pump submerge it in a light weight oil (or cooking oil for that matter) reverse the flow for a few minutes by (reversing the wires +/-) using a 12 volt power source (other than the car) and see if it clears up than put the wire back to the normal position and check if the sound has changed.
I did this some years ago I bought another pump for back-up but the original pump still works.
Best H
You can inspect the internal pump and after you remove the external pump submerge it in a light weight oil (or cooking oil for that matter) reverse the flow for a few minutes by (reversing the wires +/-) using a 12 volt power source (other than the car) and see if it clears up than put the wire back to the normal position and check if the sound has changed.
I did this some years ago I bought another pump for back-up but the original pump still works.
Best H
#4
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My pump has a low level high frequency 'whine' This is normal.
A hum that is 'loud' is usually a sign of restriction in the intake (in take pump maybe?)
I would follow the suggested procedures and see if the 'hum' goes away, however I have always been able to hear the pump if I stand on the rear right (passengerside) as the 928 (86>) pumps are actually outside .
A hum that is 'loud' is usually a sign of restriction in the intake (in take pump maybe?)
I would follow the suggested procedures and see if the 'hum' goes away, however I have always been able to hear the pump if I stand on the rear right (passengerside) as the 928 (86>) pumps are actually outside .
#6
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Thanks folks. Looks like a good winter project.