I tried messing with mine a long time ago by adding a coper cap in-line to restrict the flow-- never quite worked right. Can you tell me what method you used and if it worked. I can't stand the slow return to idle!!!!
Mine screwed up once and I removed it and cleaned it with Gummout carb cleaner. They also stick shut sometimes and cause the car to die at idle. You can free it up with a tap but gum is what causes that too.
This isn't really a problem. It's done on purpose to lower emissions. I installed this one I purchased from ebay and it works fine. It's made out of a heavy Mr Gasket gasket material so you don't need any sealant or additional gaskets. I've had no change in gas mileage either.