wiper Issue

Hope someone can help.

I have an 87 caprice classic brougham, rebuilt engine (307 4bbl) and tranny (200r4, Performance shift kit, very snappy shifts), dual exahaust. A pretty good car just has a few problems, the most annoying of which is i can't completely turn off the windshield wipers without unplugging them. When the switch is in the off position they are actually on low and stay that way. Any ideas on how to rectify this problem.

sounds like the switch is broken, might have to replace it.

I think it was replaced once and did not help. It is probably worth trying again though. If it doesn't help, any other hints.

The delay circuit board is shot. Check your grounds at the wiper motor first. There are replacement washer pump/delay units that can be bought at most major parts stores that will correct the problem.

If it is a delay system there is a diode that blows and they won't shut off IT is in your main line connector at wiper motor under weatherpack of connector To check between white and purple wires you should get 0.4 to 0.6 volts then reverse leads of tester )0.4 to 0.6 volts falls in this range it's good /not it's bad replace it's proper name is Wiper motor relay diode make sure you do things under
To test
Ign/off
connector discont
neg battery lead discont
pink lead washer level discont
This should be done if the switch has already been eliminated as been good [wiper switch]

Just a note to say thanks to every one, I'm really impressed with the speed of responses and the knowledge, haven't tried any of these suggestions yet.... To cold here. I do have other questions i will post soon, hope i get the same level of response.

unplug them under the hood. remove the other plug on the black plastic cover and then pull off the black plastic cover to access the circuit board. Spray the hell out of it with electrical contact cleaner. You may have to do it a few times. The contacts get dirty from no use. This has worked every time for me.