I have a 1989 Chevy Celebrity, with 139,000 miles on it. The wipers won't work. The motor runs, and the arms make a clicking sound. I tried another motor, with the same results. Could both motors be bad, or is there another possibility?
When you had the cowling off, with the wiper motor running, did you notice if the arms were moving? If not, disconnect linkage to motor itself. Try to move wiper arms manually. If they move freely, replace the motor. It is possible to have a defective motor. Do this only after complete visual inspection of the wiper assembly. : D