I have a 1997 V40 wagon with a 2 litre non-turbo engine with 139000 kilometers on it. Recently after cold startup there is a noise from the electric motor fitted under the fuse box on the left hand side of the engine bay. The motor only runs for about 2-3 minutes after the car is started and then you can hear it spooling down to a stop. The unit has a hose connected to the air inlet manifold downstream of the air filter. It looks like it would be quite easy to replace once the fuse box is removed.

The motor doesn't seem to be spinning [or at least making any noise] when the engine is warm.

I figure that there is a bearing failure in the [sealed] electric motor, and my freindly local dealer is quoting $1360.00 to supply a replacement!!


My questions are; 1. Has anybody else had this problem?
2. What is the function of the air pump, if that's what it is?
3 What might be the consequences if I live with the noise and
the electric motor siezes?

the air pump is a auxillary vacuum pump for the brake servo. The pump cuts in if there is not enough vacuum in the brake servo to stop the possibility of a hard /poor brake.

The vacuum from the inlet manifold should create the vacuum for the servo but at times it does not provide enough vacuum. Thus the need for a auxillary pump.

The pump is not supposed to run all the time and it is quite noisey when it runs (can hear it in the car) are you sure you actually have a fault?.

Thanks for the quick response raydar. I would never have guessed it had anything to do with the brakes!!

The "fault" is the extremely noisy running during the 2-3 minutes that the pump operates after a cold statrt up. This is a very recent developement,[six weeks?], and my [semi-educated] guess is that the armature bearing[s] in the electric motor are either shot or on the way out. It sounds like a jet-engine starting up and then spooling down!

I can put up with the noise, although you do get some funny looks in the car park, as long as I am assured that it will not effect the safety or proper operation of the car.

However I have reached the limit of my technical knowledge, so is there any liklihood that a complete electric motor/pump failure would make the car unsafe?

Thanx again.

There is a chance if the pump seizes that you may experience no servo assistance for your brakes. If it is indeed overly noisey I would replace it.

The price quoted seems over the top though by far, you could fit it yourself in half an hour.