Bizarre windshield wiper behavior...help!

Background info: A few days ago, the heater blower motor on my car seemingly broke, and my father was going to replace it today. He removed a panel to get to the motor and found that there was a mouse nest causing the problem, there was nothing wrong wtih the motor itself, he removed the mouse nest, problem solved. Also, I washed my car, refilled my windshield wiper fluid, and put in two quarts of oil several hours after this.

Driving to work immediately after my dad working on my car, my wipers worked fine, they were totally normal.

After work, I’m driving home, and I flip the little lever that sprays wiper fluid on the windshield and starts the wipers. All of a sudden, my wipers are working backwards. You know how when you shut your wipers off, they go down, pause for a minute, then sink into their resting positions? It was just like that, only instead of going down, pausing, and sinking into place, they go up, pause, and then move all the way up so they’re straight up and down. Hope I’m describing this well enough. Basically, they’re working fine, only in reverse.

Anyway, I’m going on a long car trip tomorrow, and this is going to annoy the hell out of me. Has anyone ever seen anything like this? Is there anything simple that I can do myself in the morning to fix it before I leave?

I don’t know much about cars, but it sounds like your father accidentally messed up the linkage between the wiper motor and the gears that actually drive the blades. Moving this linkage back to the correct problem will probably fix the problem. But it may take a bit of trial-and-error to find the correct position.

Some cars (used to) requre you to open the linkage to adjust it. Some allow you to simply move the blades manually. Some wiper problems (usually, but not solely, desynchronization) can be fixed by undoing the bolt that holds the wiper arm, and adjusting the arm. Check if the reversal switch is electrical or mechanical - but un your case, I try to fix wipers at the same place they got maladjusted in the first place.