After washing the engine, engine cranks but does not start?

After doing an engine wash, the motor only cranks but can't start. Checked the fuel system and all the 4 injectors firing at the same time. I replaced the plugs but nothing, when I removed the plugs, they came out wet and black, and checked the distributor could see a spark from the plug when cranking the motor. Right now, I am stuck and don't know what the problem could be.