Oldskeeper

I've got a 2002 Olds Bravada and the windshield wipers do not act properly in pulse mode. On the return movement they jam with a start/stop motion. The wipers work fine on full and on highspeed. Has anyone heard of this or if there has been a recall? We have had this vehicle for two years and just recently started doing this. Any tips would be great.

Thanks
Steve.