'00 S40

[DouginDenver]

I'm sure this is a normal noise, but I'm just wondering what it is. My C70 has no such noise. It sounds like real short burts of a small humming electrical motor, like a fuel pump would sound. It's faint enough that I only hear it while sitting still on a quiet street, or like when parallel parking in front of my house. I can only say it sounds like 2-second bursts from a faint fuel pump, but it sounds like its coming from near the firewall behind the steering wheel. What the heck is that?

[theForgottenone]

I'm sure this is a normal noise, but I'm just wondering what it is. My C70 has no such noise. It sounds like real short burts of a small humming electrical motor, like a fuel pump would sound. It's faint enough that I only hear it while sitting still on a quiet street, or like when parallel parking in front of my house. I can only say it sounds like 2-second bursts from a faint fuel pump, but it sounds like its coming from near the firewall behind the steering wheel. What the heck is that?

brake pump for the resevior

[JAGMAN]

brake pump for the resevior

Correct. There was a recall a few years ago that replaced and relocated the brake assist vaccuum pump. It was moved to the area just behind and inside the left strut tower. The result of the new location is that it is noiser, but will stay dry and won't get ruined over time. You can verify that it is the brake vac pump by doing the following. Start the car after it has sat over night. Then with the car in Park press and release the brake pedal rapdily, you should hear the pump cycling on and off when you do this. It makes this noise far less after the car is warmed up.