So last weekend I replaced my DPFE, EGR, fuel and air filters, did an oil change, and began flushing my power steering fluid. I replaced the DPFE because the vehicle was idling rough, and this forum prompted me to check that item. It looked fried, so I replaced it. The EGR valve was replaced because I pulled my UIM off to clear a mouse nest out, and it broke. The rest was just maintenance. After zero change in the idle, I pulled codes, and got 176, 327, and 411. Do I really need to do an O2 sensor on top of everything else? She runs fine while driving, but has a slight RPM stumble in idle. And pulling the vacuum hose off the EGR valve makes no change. WTF? Oh yeah. The AC compressor doesn't kick on either. I was also considering a vacuum leak. I ran a propane torch around but got nothing. Ideas?