I'm in the market for a 14' cayenne gts, and i'm aware that pretty much all GDI engines are prone to carbon deposits... at any rate i would like to know if someone knows the cost of the procedure and how often it needs to be done.
I've done some reseach online but i can't get an acurate cost.

 

It really depends on the dealer. I have heard anywhere from $1000-$2000 so it is a wide spread. I'm not a fan of the DI engine unless it is a "hybrid" type design like Lexus has. Keep in mind that walnut blasting can cause cylinder scoring so it's best not to do it too often.

 

Do they actually do it in the car?? Seems like a recipe for disaster to me but I suppose someone has figured it out.

 

Yes, otherwise the cost would be triple what I quoted. In my opinion it's best to trade the car in before this service needs to be done.