My brother had the same problem. His company car had the air cleaner and intake manifold packed full 3 times. Fortunately (for him) the company service plan payed for it - more than $1000 each time.
He found a product that smelled like Coyote urine at one of the big box hardware/lumber stores and spread it on the ground around the tires. He had no more problems so long as he reapplied whenever the car was moved.