Having an issue with the wiper motors I believe, though not sure exactly. It only works when the switch is turned all the way over on constant, for a little while... Then it does this:

https://youtu.be/aMf_HsAOMWw

What's going on?

 

go to the "sticky" at the beginning of this forum ... 'Read first 1987 - 1996 tech info ' ... interm ittent wiper fix... this may well solve your problem.

 

That was good to read, but I don't think that's the issue, but I could be wrong!

The wipers only run when the **** is turned to one spot, and I believe it's the fast continuous spot. It'll run perfectly fine for about 2 minutes, then it will start to become intermittent, as you see in the video. The longer I keep the wipers engaged, the worse it gets. If I turn them off for a while, it gets better again.

I don't have a problem with them 'parking' at the base of the windshield at all.

Seems like the motors are shorting out and/or overheating or something, right?

 

I'd first look to see if the switch is bad. You should be able to disconnect the plug at the motor, then connect it directly to the battery and see if it will run continuously. If so, the motor should be ok and you should replace the switch.

Next, pull the motor off the firewall, plug it back into the harness and run it with the switch for control. Don't touch that rotating arm - it's a powerful little motor that could hurt your fingers.

If the motor moves well in all switch positions, then the problem may be in the linkage between the wiper arms. You can lube the pivots for the two arms with penetrating oil, but you need to remove the arms and the cover plate behind the hood to lubricate the ball linkages that connect the two arms (at least that's what it looks like on my 1989). You might just want to lube the pivots and move the wiper arms by hand to see how tight they feel.

If the motor itself is bad, it's not too hard to pull them apart. There are several problem areas with most wiper motors:
(1) dirty/corroded electrical contacts on the wheel internally,
(2) the main shaft that turns the wiper arm is corroded,
(3) the bearing on the motor far end is corroded,
(4) the brushes on the motor are worn out.

(1) The internal contacts (they are "wiper contacts" which has nothing to do with them being in a wiper motor!) can become dirty. Clean the grease off the plate with the copper plating and use a rubber pencil eraser to clean the copper to bright metal. Do the same for the contacts. Bend the contacts to apply a little more pressure to the plate when reassembling. Wipe "fresh" grease that's inside the housing onto the contacts - yeah, wierd, but it works.

(2) The corroded shaft can usually be sanded, wiped clean, greased and reassembled. You may need to use a hammer to tap it out.

(3 and 4) See that the motor armature itself turns freely. If it doesn't.....Taking the armature out of the motor is the hardest thing, and there's a good chance you won't fix it. The bearing (oil impregnated bushing) is more work than it's worth to replace, and I don't know if you can even buy the brushes. If you do take it apart and the brushes look ok, you can sometimes flip them over (pull out, rotate 180*, reinsert) and get a few more years out of them.

The good news is the motor is only about $60, so it's no big deal if you can't get it back together - and you might get lucky by taking it apart.