fan on when starting car

[Jayx5]

Every time I start my x5 when cold the fan runs and sounds like a space ship going down the road, it lasts about 200m and then cuts out. Does anyones v8 do that?

[Ryoken]

mine does the same , isn't it the AC fan firing up as well ?.

[Jayx5]

Mine does it with the air con off!

[X5Sport]

Have you got it in a recirc mode?  Just thinking out loud.

Richard

[Smeeagain]

[quote="jayx5"]
Every time I start my x5 when cold the fan runs and sounds like a space ship going down the road, it lasts about 200m and then cuts out. Does anyones v8 do that?
[/quote]

What make/model/year of space ship does it sound like?

Smee

[Jayx5]

Lol, it actually sounds like a old 2.4 diesel toyota engine! The fan does seem to come on a lot when driving as well could it be a dodgy thermostat?

[davesavage257]

There are two fans on the X5, the main engine cooling fan (between the radiator and the engine) and the auxillary air con fan (in front of the radiator, behind the grill).
The main cooling fan is driven by a viscous coupling, old way of testing is to roll up an old newspaper and carefully push into rotating fan blades when running. If it stops the fan you need a new coupling. A good coupling will bat the newspaper away.
The auxiliary air con fan is electrically driven, switched by a PWM signal from a control box.  It should run when your air con is on to help cool air over the condenser.
The normal failure of the aux fan is to stop running, it may just twitch if you watch it when the snowflake air con button is pressed with engine running.
Hope that helps.

[Jayx5]

Ok thanks will give that a try.

[Ubatoid]

Perfectly normal. what happens is the sticky goo collects in the bottom of the viscous unit when left for a long period and this locks the fan until centrifugal force puts back on an even coating. The pusher fan should do a quick self test when starting, ie a quick spin up and then stop.

[Jayx5]

Nice one that's put my mind at rest until the next problem. )

[X5Sport]

Nothing like a new bit of viscous coupling.........ask 535dboy >:D