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+--- Thread: Humming sound (/showthread.php?tid=10646)
Humming sound - Mrkentee - 06-24-2026
I’ve read about oil pump noise ( and I’ve noticed that before with the new style oil pump) , or power steering pump, or maybe fuel gear pump.
This one is only noticeable when driving with light pressure on the fuel pedal. If you let off, or press down and put a load on it, it goes away. Hard to tell what it is.
Edit: it’s a CM871
RE: Humming sound - Rawze - 06-24-2026
maybe this post helps...
https://rawze.com/forums/showthread.php?tid=5184&pid=70510#pid70510
RE: Humming sound - Mrkentee - 06-24-2026
(06-24-2026 )Rawze Wrote: maybe this post helps...
https://rawze.com/forums/showthread.php?tid=5184&pid=70510#pid70510
I forgot to mention it’s an 871
RE: Humming sound - Rawze - 06-24-2026
just throwing thoughts at the wall here...
It can also be the accumulator in the A/C system causing a hum too. very common as they wear out.
RE: Humming sound - Mrkentee - 06-24-2026
(06-24-2026 )Rawze Wrote: just throwing thoughts at the wall here...
It can also be the accumulator in the A/C system causing a hum too. very common as they wear out.
Shut off a/c no change.
Parked with hood open varying rpm, can’t duplicate. Almost sounds like air going through something.
But definitely stops when I let my foot off the pedal when driving.