I pressure washed the under hood of my 98 grand Cherokee 5.9 limited and it would not start after that.

I had to remove the plug on the coil and blow water out of it then plug it back in.

the weather proof plug goes in from the bottom on coil and makes a cup that will fill with water and short out the coil.

I put some di-electric greese in the plug holes and pluged it back in.

you may need to replace the coil or at least dry the plug out.