I've never heard of one myself, but I really dont know all that much.....
There have been people that have replaced the whole thing because of that particular problem, and it cured their woes, so you might have to go in that direction.
I'll try cleaning it. I bought gumout throttle body cleaner. It says to use the whole friggin bottle! I'm positive it's not the cable because it has full travel with a bit of slack. Seems like the linkage to the lower throttle valve is sticking. How much freeplay should there be in between the upper valve and the lower one? There is a stop screw, is it wise to mess with that? Could it be out of sync? How do I adjust this sucker?
There are two hoses about the size of a nomal sharpie marker on the very bottom of the throttle body. Other thant hey are very difficult to remove in such a tight place and maybe that was due to someone cut them off the first time, I don't know.
All I know is that there wasn't enough slack to get the throttle body up where you could work on getting the hoses on and off.