This my first post I have owned several Chevy and GMC trucks the last 30 years, I currently drive a 2007 Z71 Tahoe with 180K miles. My 2007 Tahoe 5.3 LMG briefly flashed the CEI and Traction Control lights on Wednesday afternoon and went off, didn't notice any performance issue while going 75 to 80 mph, the next morning it did it again at highway speeds and stayed on a bit longer but went away, that afternoon it came on and stayed on. I've checked for intake & vacuum leaks, fuel pressure and trim, compression, injector plugs are pulsing, and have spark. My scanner tells me that #4 cylinder is misfiring 490 count, #3 45 count and #2 28 count. I just changed the injectors about 14 months ago. Regardless I have compression and spark so logic would assume the fuel is missing, I'm replacing the #4 injector today. Am I missing anything, if I have compression I shouldn't have a collapsed lifter. We'll see what happens with the new injector... If any of you have a suggestion please opine.