I've been posting on this site for a while now and have not received any viable solutions. I've checked everything replaced all of the maintenance items fluids plugs wires timing chain gaskets all the vacuum lines have been checked and all of the engine and Chassis ground are good ECM sensor grounds are good or at least have continuity. just last night had check engine light come on with code 71 for egr malfunction blah blah blah. here's how the misfire works it happens only above 2000 RPM's and sort of stumbles and hesitates. no loss of power and no actual misfire trouble code has ever been retrieved from ECM. I've done the TPS check and afm replaced. nothing I did or check has ever seemed to make a difference. now I would like some advice on how to definitively check my EGR system. also I should mention that there was a couple of electrical malfunctions. first one was after I checked all the engine and Chassis ground I found one was missing from the cylinder head to firewall replace that wire and as soon as I turn the key to start it up there was a big spark near the battery for fuse box. unfortunately that electrical short took out my battery had it replaced with another problem has not reoccurred. at another point I had been looking for 8 possible short in my wiring harness by doing the usual wiggle test. when I was moving the harness around I somehow shorted out a 15 amp fuse. I replaced the fuse hasn't happened again. now I guess my questions are if the truck has been misfiring and stumbling ever since I bought it then what should I check next? I've replaced plugs wires injectors 02 sensor Upstream coolant temp sensor check and set TPS sensor and AFM. I know my post here is kind of long and erratic but I am always on this site and more than willing to answer any questions for viable diagnostic advice. Thanks