My truck has a slight stumble/misfire at idle only and is worse at temps above 40 degrees. Has never set a code since I got it last August 2013. Scan tool last fall showed highest misfire counts on #2,then#4, then#6 and once in awhile ,1 and 3. The misfires all disappeared at 1500 rpm's and higher.
Recently did aluminum plenum plate repair and a double roller(Cloyes) timing set. This has improved overall power and idle isn't as jittery. I ohmed the injectors and got 13.8(2), 13.6(4), 13.5(6) and 13.3 for(8). Are these far enough out of spec of 12ohms per FSM and is that the right spec? Compression Is good, ignition components are good, only thing I haven't done is a leakdown. New fuel pump also. Some of the locking tabs were broke and I broke some more as they are brittle. Kind of makes sense,aye? Has 89,000 miles now and plugs are still white.

 

That's close enough. Should be a problem. (at least, in that respect)

Another member had similar issues, replacing his crank sensor with an OEM part fixed it. Whether that will fix yours.... open to question.

 

You only have 89k miles? Where did you find that truck hahaha

I have broken so many locking tabs on my truck its not even funny. Dang things are just there to annoy us anyway.

 

Seattle WA, on autotrader. Bought One just like it from Kansas City MO.,with 57,000 mi last Jan,2013 only was gold. Totaled it and two other cars April 5th,2013, 500 feet from home,Ouch!. There out there. Found a 98 with 26,000 miles but the old lady was giving it to her grandson and wouldn't sell.
In reading about injectors recently, it seems a lot of crud builds up on the even bank fuel rail.

 

Part of the reason for that is because we do not have a return-style fuel system. Anything that makes its way to the rail, stays there....