Hey guys: My revs don't come back down to idle when I get the clutch down. They stay at like 2000 RPM until the car stops and then like 2 seconds latter come down. This only started happening when the dealer installed some new software load, but I can't imagine that this effect was intentional. On a simpler car I would just clean the throtle body. Have any of you guys dealt with this?

Thanking you in advance,
Asim