I have a Kenmore front load washer that is flashing a f21 code. I have replaced the pump and the pressure switch. I have checked all hoses and everything is clear. What else could it be

Why did you replace the pump and pressure switch? They have nothing to do with an F21 code. An F21 is a restriction in the drain and means that the pump and pressure switch is working fine. Those are two parts in an F21 code situation that you know are good. Look at your drain. See: https://dl.dropboxusercontent.com/u/8010163/Kenmore_Washer_Elite.pdf
https://dl.dropboxusercontent.com/u/8010163/Understanding%20automatic%20washer.pdf
I cannot understand why so many insist on making parts suppliers rich. Always check your parts with a meter first. There are simple ways to test them with a meter and when they test good you look elsewhere.

The pump was bad. The empellor was spinning free on the shaft. I checked all drain hoses there is nothing blocking it. Now when you turn it on it wants to go straight to spin cycle. There's no water in it because I drained it out. Is it shot

You have an electrical problem that you will have to find with the meter. It should not be too hard to do.