So I was driving to my parents house yesterday and no problem with my truck running great as always...go to get on the freeway and at 70 or so mph (2500rpm) it starts to miss and the check engine light starts to flash... great a misfire. So get the code scanner out and cylinder #3 is pending for a misfire...so i get off at the exit and starts driving fine light stops flashing driving like normal... Get to my parents house just did a quick look around the engine bay... Everything is intacted... I'll add that i did a tune up (plugs, wires, and coil all FOMOCO) about 7000 miles ago. So driving home after doing the work i had to do it was fine until i got on the freeway and was doing 70 again...Dropped down to 65 and no issues what so ever and drove fine all the way home not a single issue after then this morning on the way to work the light is just on...So i parked it and said ill look at it at lunch. So go to lunch and its missing bad. you can feel it shake the truck...So i let it cool down and pull the plug and check the coil and wire for a crack or something...plug looked brand new no signs of fouling or lean. Put everything back together...started the truck and ran totally normal not a single issue light went out. put it in gear didnt miss and ran great....HAS ANYONE RAN INTO THIS PROBLEM.... Maybe an injector problem??

 

it could be alot of things, some things to ask:

what initiates the misfire? light or heavy load?
does it do it when the truck is warmed up or cool?
how many miles are on the motor?
how old is the cat, it could be clogged?

if it were my truck i'd start with checking the usual, fuel pressure, compression, signal to the injectors, etc... it could be a faulty coil. check to see if your getting a spark, and that ALL wires are tight and have a clean connection points. i cant tell you how many times i have seen hundreds of dollars spent due to corrosion or a loose wire. injectors arent a bad idea, just an expensive one. or at least more money than im sure you wanna spend. take the truck out and play around, see what pisses her off. try to duplicate it at a lower rpm. i've got a 99 3.slow, their tricky lil motors when they get problems like this, but almost every problem i've seen on mine has been nickle and dime fixes. keep me posted man!