Had the pleasure of replacing the wiper motor over the weekend. Got the new one in and optested it... it runs but sounds like it is working too hard and going really slow. Checked the BlY input and get 10.8 VDC. Checked the battery and read 11.3 across the terminals. This car has got some electrical issues... Any suggestions where to start? I checked the ground feeds coming in from the wiper switch at the other 2 terminals foolishly thinking I'd get a solid ground, but there is a capacitor inline there somewhere and the reading fluctuates.

I think I've got a ground issue somewhere, but where to start???

Any help?

Thge electrical power takes a journey from the battery to the rest of the car.

Measure from battery positive post to the hot wire on the wiper connector. Voltage drop should be less than 0.4 volts. If more, then you need to clean terminals. Start at the junction block behind the battery and clean there. Then, jump over to the horn relay underneath the voltage regulator and clean there. Then, separate the firewall connection and clean those. The wiper switch applies a ground when wipers are selected.

Also, a dry windshield adds to the friction to overcome, making the wiper motor draw more power from the battery and this action will drop the battery reading.

Might not hurt to charge the battery also, s/b 12.6 volts for a 100% charge.