Additional (electric) Water Pump Noise

[Pipes]

I was just wondering if the electric water pump is supposed to be:

1) Pretty loud
2) The RPM's of the pump increase and decrese constantly. I think the pump should run steady in all conditions?

Does anyone know if there is a sensor to control the rpm's of the pump, or if it's the actual pump gone bad?

Thanks

[The Cleaner]

The pump that goes to the heater core? it's not constant but should not make noise.

[Pipes]

yeah I'm pretty sure that's were it goes.

So the rpm's should alternate depending on some factors?

Yeah, it makes a buzzing sound that I can hear from the interior with all windows closed, and the buzzing goes up and down, it's really annoying.

I was wondering if there's a sensor controlling the speed of the pump thats gone bad...

Thanks

[The Cleaner]

Turn off you climate control and see if it still make noise. There are 2 electric valves that regulate the water flow, maybe they are making the noise.

[Pipes]

I actually tried that already. The noise is coming from the pump: I can hear the noise only with the climate control on (fron under the hood), and If I wiggle the pump the rpm's start oscillating even faster, which leads me to think its a bad pump. I would just replace it but at $250 for a dinky electric pump, I would like to know if that's the problem for sure. I was thinking there might be something else controlling the speed of the pump gone bad... maybe I'll check to see if there's a constant voltage going to the pump.

[drs]

Just had my X to the dealer yesterday. Sitting at traffic light and I hear this kind of moaning sound going up and down. When I turn climate controls down to 60 degrees the sound goes away. Dealer said it’s the secondary water pump or heater control valve. They are replacing under warranty. It’s also covered under CPO warranty.

Had a pixel question……………..

Some of the pixels in my mileage display went out for a while and came on again in the same day. Are they on there way out???

drs

[cue03]

Anymore word on this. I think i have this problem also. Dealer actually had the nerve to tell me they all make this noise. i went and sat in 3 more 4.8is vehicles today and NONE of them made the noise. when you turn off the fan/AC completely the noise stops which leads me to believe it has something to do with the AC.

[X5Flyboy]

mileage?? - previous posts indicate the water pump gives up the ghost between 60K-80K miles - I replaced mine in the '01 at 61K due to my long trips - cheaper to fix in the shop than out on the road

3.0 engine? There are some advertisements for an aftermarket waterpump with stainless steel impeller (vs the plastic BMW impeller waterpump) - I have not seen one for the 4.4, 4.6, or 4.8

[cue03]

I have 4300 miles on my truck. It is a 2004 4.8is

[Pipes]

I changed out the auxilary water pump, noise almost dissapeared. If I listen closely under the hood, I can still hear the pump rpm's go up and down though, not as load as before though. I think it's suposed to do this? It happens when I set climate to about 22 degrees (celsius). I think the heater valve opens and closes, which causes the pump to make this noise.