I have a 1999 C5 Conv....80000 miles, auto. left town for a few days .... drove the car for the first time after returning ..... used the wipers to clear the windshield and they would not return to the park position. later that day driving home, they turn themselves on the delay position with the switch off....  any suggestions ???  

I would try resetting your battery. I dont thnk the motors are burned out.  

My wipers do the same damn thing, and I have an 05 z51 c6. Anyone else have some advice?  

OK, basic knowledge from what I have learned on my 86.

There are adjustments under cowl vents where the wiper arm transmits direction from the motor.  They are adjustable to keep one arm from colliding with the other.  the holes where the nuts and bolts go are actually slots and from what I have found they seem to vibrate loose or else the second owner didn't know to adjust them when he replaced the motor.

86 wiper arms only go on the transmitting stems one way,  they are keyed.

The motors generaly have two switches on them one is the parking switch which brings the arms down when you turn them off.  The other switch is the pulse relay circuit board.  It controls the intermittent, lo, and hi speeds of the wipers.  

Some of the newer units have the wiper washer pump built into the housing that holds the pulse relay circuit board.

Then you have the control switch which on an 86 is built into the drivers door and only has one wire that plugs into the harness, and you do dot really want to take the door panel apart if you can avoid it.  

What my experience has shown me is that the Wiper motor is mounted so close to the engine that it picks up engine heat and just Flat wears out. and when it wears out the Parking Switch goes too!!!

I did some electrical circuit testing with a VOM (Volt Ohm Meter (Digital)) and I AssUMe-d my pulse relay circuit board was still good. Since the previous owner had the receipt for the new switch in the door, I replaced the wiper motor for about $70.00 because the park switch was built into it.

Now that I have my arms adjusted and the new motor in the wipers work on lo and hi.  They park where they are supposed to, come on and go off when told to, I just have to replace the $125.00 pulse relay circuit board, when I can find one for a reasonable price that has not been cracked by the distributor or the Intake Plenum.  

To bad you can't use one off a silverado as they are only $35.00

I hope some of this helps some of you fella's.  Most people you see driving Corvettes don't drive in rainy weather, maybe this wiper problem is why.  I had several british TR - 2's and about the only thing that did halfway work in the rain was the wipers. Not the gauges, or the lights, positive ground, you know(LOL)

RedCorvette86