2007 Silverado Wiper Component issue

It sounds like the wiper motor has a problem with the park signal generated from the motor cover. If you remove the motor cover, you can see if the round wheel with 4 legs in a star type fashion is securely on the motor cover or not. Do the wipers work in the delay mode or not? The delay wiper function is based on the park signal of the motor and without a clean park signal, normally the wipers will run in low speed instead of delay.