This will show you how to replace the fuel pump on the 2011 Fiesta.
The only tool you need is a screw driver.
So here we go:
1. Remove the rear seat cushion. There are two clips just under the front edge of the seat about 8" or 10" in from either side and 1.5" to 2" from the front edge. You might be able to see them if you have a mirror and a flashlight but you can feel them under the front edge of the seat. They both push toward the passenger side of the car to release the seat cushion while you are pulling it up.
Here is the passenger side
And driver side
Here is the clip after the seat is removed
Once the clips are loose you have to push the cushion towards the rear of the car and then lift up to get the seat cushion out.
Here you can see the three clips at the rear of the seat cushion
Here is a close-up of one of the clips
After the seat is out it looks like this
2. Now pull out the 8" dia. rubber cover
3. Unplug the electrical connection.
4. Unclip the blue clip on the fuel line.
5. Use a screw driver and hammer to tap the 6" dia. locking ring counterclock-wise. You're done.
The only tool you need is a screw driver.
So here we go:
1. Remove the rear seat cushion. There are two clips just under the front edge of the seat about 8" or 10" in from either side and 1.5" to 2" from the front edge. You might be able to see them if you have a mirror and a flashlight but you can feel them under the front edge of the seat. They both push toward the passenger side of the car to release the seat cushion while you are pulling it up.
Here is the passenger side

And driver side

Here is the clip after the seat is removed

Once the clips are loose you have to push the cushion towards the rear of the car and then lift up to get the seat cushion out.
Here you can see the three clips at the rear of the seat cushion

Here is a close-up of one of the clips

After the seat is out it looks like this

2. Now pull out the 8" dia. rubber cover

3. Unplug the electrical connection.
4. Unclip the blue clip on the fuel line.
5. Use a screw driver and hammer to tap the 6" dia. locking ring counterclock-wise. You're done.