sometime when i start my 2000 discovery a fan in the dash runs and is obnoxious. but if i shut the truck off and start it back up the fan is off. does anyone know what that might be?

 

That is a strange one, where do you have the a/c or heater controls set when this happens?
Mike

 

sorry about the late response. i checked on that today and the heater and a/c were off but the fan noise still was there. however sometimes it happens and sometimes it doesnt. when it does i can either wait like a minute for it to shut off or i can turn the engine off and restart it and it stops. i noticed the same noise in other disco's i drove so i didnt think it was anything abnormal. but it is annoying

 

This is not normal, I wish I could tell you what to look at but I haven't run into this before.
Mike

 

Could it be that your fan speed regulator is going bad? Not very sure though as your problem seems odd to me.

 

I think I have this same issue. Only on the first startup of the day does it happen. But on start up I get a fan running sound. Only lasts about 30-60 seconds and shuts right off. I thought it was normal warming up- but if it is a problem I need to figure out what it is...

 

that is exactly when it happens. when my vehicle sits for a long time like when im at work all day or when i get in the morning after sitting all night

 

I would suggest that either of you might call and speak with the service manager at you local dealer, ask him if he has heard of this and go from there.
Mike

 

Mine does the same, I just figured it's normal. It seems to come from the engine bay, not the dash - it is unrelated to the A/C system. Almost sounds more like a pump than a fan - I thought it may be the fuel pump priming or something. Never lasts more than 15-30 seconds.

 

It is not the fuel pump priming, what year is your truck? May be the ABS in your case firing up and doing a self test that it supposed to do every time you start the engine. How long has it been since you changed your brake fluid?
Mike