Did you check the other ends of those heavy gauge wires?

Also, the four stupid wires that ground to the dip stick retainer stud.

 

Timing chain jumped.

 

I've washed the engine bay down on all three of my cars many times and never had an issue. The sole exception occurred in my GTI a few years ago, and the only issue is I'd get a misfire at more than half throttle or so when I first drove it. The VR6 uses a single coilpack, and it must have been arcing when it got wet. Never had a problem before or after, and it's still on the original ignition system.

What I do for the Cherokee and most other cars is take a piece of aluminum foil and cover the brake fluid reservoir. I figure this keeps unnecessary moisture away from the fluid since the cap is vented (I think). I also do the same for any dipsticks, since those o-rings aren't exactly watertight. I use one of those garden wands with a head that has a zillion tiny holes (exact one pictured below). This gives me good volume but low velocity. I hose down the entire engine bay and don't worry much about the electrical bits. To finish up, I take my shop vac and suck up all the water. Works fine, but maybe other cars are more susceptible to water issues. The suggestion above about disconnecting the battery is a good one. I've never done it, but it's not a bad idea.

 

Hope you get it figured out! I haven’t ever degreased and washed my engine bay in the 7 years I’ve owned my Jeep because this is exactly what I am terrified of haha.

 

Update: Got the Jeep started last night. It was the Crankshaft position sensor, but I am glad that I took everything apart because I found that both my spark plugs and my ignition coil pack was about to go, and I'd rather replace it now than on the side of the road. Thanks to those of you that helped and gave advise.

I am not afraid to throw money at the engine to replace 20 year old factory parts and sensors, because it truly cannot hurt anything to have new electronics.