Yep, GM has their "Top engine cleaner" which is available in an aresol (sp?) form that can be sprayed into the intake behind the MAF and a liquid version that can be used with a special canister that hooks up to the schrader valve and cleans the injectors as well. It's good stuff

The benefit of Sea Foam over top engine cleaner is that, from what I'm told, Sea Foam can be put into pretty much anything: gas tank, crankcase, transimission, motorcycles applications, two stoke enignes, margarita mix, and a crapload of other stuff.

 

Discount Auto in Northdale has it.