I already had the DPFE Sensor changed and the Service Engine Soon Light is still on. So I had them run the code again and it still says it's my EGR Valve so I was going to change it myself (well my fiancee and dad). The DPFE sensor was impossible to get to they had to remove my whole engine to do it I was hoping this would be a nice easy job we could do at home? How do you do it?