Need help figuring out what's causing my Explorer to run bad.

My 95 explorer idles rough(engine bounces a little), "studders" under acceleration for a few seconds (usually around 40mph and 60mph), and gets terrible gas mileage. I pulled the codes using a KOEO test and got hard code 335 and continuous codes 157, 332, 327 and 543. I did some research on code 335 and most people said it refers to the DPFE sensor and recommended replaceing it. I've replaced the EGR valve, DPFE sensor, air filter, cleaned the MAF sensor and cleaned the coil plate. I inspected the hoses from the EGR sensor and they were fine. I thought replacing the DPFE would solve my problem, but it didn't. It still runs the same. And the CEL still lights up. What else can I look for that would cause those symptoms? The only other thing I could think of was to replace the EGR valve position sensor too. Not sure if that would help.