What casues sporadic windshield wiper operation in my 1992 Chevy K1500 Z71?

Answer 1

Typically, it's the park switch inside the wiper motor. The motor has an internal switch that keeps the wiper motor running until the blades come to the "Park" position. If the internal switch is damaged or worn out, you'll get exactly what you're seeing.

AnswerI had the same problem with my 1998 Chevy K1500 Silverado Z71. I took it in to the Chevy dealership and the guy told me that it was a very common problem in the 1988-1998 (I believe those were the years) Chevy truks. Anyways, he told me it was a wiper module and that they were infamous for doing that. So I bought one from the dealership for about 40 bucks and installed it myself. It's very simple to do; only three screws involved. So all you need is a screwdriver. The module is located right in front of the wiper motor (on my truck). Hope this helps. Answer

To add to the answer above, yes it's a common problem but it's an easy fix if you want to save some money. The circuit board inside develops cracks in the solder spots causing the wipers to run sporadically. In my case sometimes the wipers would work, sometimes they wouldn't. I did research online and found this information on www.ChevyTalk.org on how to fix it:

http://www.chevytalk.org/fusionbb/showtopic.php?tid/201653/

Scroll about half way down to the post with the picture. I just fixed mine yesterday and it worked after a test but I don't know about long term yet. I fixed mine 2/21/12. Thanks "someotherguy" for the post!