I own a 2004 F150 Ext Cab LB 5.4. Recently, the blower motor takes 5 - 10 seconds to start blowing when I turn on the AC or the vent. I first thought it was a vacuum leak but cannot find one. It happens after sitting in the sun all day and is intermittent. It does not occur in the morning after sitting all night in cooler weather. Any ideas on how to fix would be greatly appreciated.

 

I have this proble too but dont know where to start.

 

I'm not sure about your problem, but I have had a case that rodents stored dog food in the blower cage. Unbelievable? Yes, But true, none the less.