Code P0307 Miss fire cyl #7

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Joe-ty

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So I keep getting a flashing yellow check engine light when I accelerate my Yukon. This repeats every few days for about 20 seconds or so and then kicks off. I clear the code with my OBD2. I have all new plugs and wires. Most recently I swapped around plugs, wires and ignition coil with cyl. #5. I also checked to see if the lifters for #7 was working and all lifters 1, 3, 5, 7 are working. No tick noise. I cleaned mass flow sensor. It didn’t need it but I did so. I’m baffled. Should I have a shop clean the injectors for $356 or should I replace the fuel rail assembly? Might as well replace that assy since I have it open. 2015 Yukon SLE 2wd 117,500 miles.

My first miss fire did shake my vehicle and my cluster lit up like a Xmas tree and was starting to ride rough until I was able to park it. All within a few minutes occuring at an intersection. I turned the car off for an hour and then it ran okay after that but still getting the flashing check engine light every few days.
 
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swathdiver

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I think you have a collapsed or partially collapsed lifter on #7. Maybe a bent pushrod but you won't see that unless you pull the rocker cover.
 

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