You may have emissions test problems like I have been going through this month (12/2013). There is a nice guy at my emissions testing place helping me. I've been fighting the "check engine light" because the computer for Cal DMV fails my Ranger (2.5cyl 4). All other aspects pass. I replaced the Delta Pressure FE unit ($34 at Rock Auto) and that solves all the codes except....tada! EGR. It's tricky to reset the computer, according to my "Nice Guy". Disconnect battery for a bit. First start of engine, go nowhere, let it idle five minutes. Fill fuel tank to 80% full (to set vapor emission test...phfllltt!) and sit overnight (no, I'm not making this up). To reset EGR monitoring, drive about ten miles on the freeway, never exceeding 55mph. I keep failing to do 55mph for ten miles, and the light comes on while I'm driving...sheeeit!!, and after 3-4 days of around town, working perfectly. There are five tests, and you must pass four, so mebbe you can sneak by without EGR, but I gotta see if my EGR is plugged/dirty/nonfunctioning.

Thanks for the picture of the EGR valve.