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Misfire diagnosing 4.2 S5


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So to start, i have a 2008 S5 with the CAUA 4.2 V8. It has 100k miles and about a month and a 1/2 ago it began getting misfires in cylinders 1 2 and 4, so i went about diagnosing, plugs, coils, etc.. wasn't them so i moved to injectors, pulled off manifold, both fuel rails and replaced the 3 injectors on the problem cylinders, replaced all 8 o rings along with the intake manifold gaskets, and now im still having the same problems.


Some back story - Cold starts have gotten noticeably quieter, much slower, sluggish, sounds muffled almost, feels like its running on half the cylinders. If I get the car above 4k rpm a flashing engine light comes on for a few revolutions and then goes back to steady engine light. 


ive attached my VCDS scan below.



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im not too sure, i didnt mess with any of the cam or crank sensors, and only messed with the maf sensor by removing and reinstalling the intake pipe

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On 6/16/2024 at 5:24 AM, Steve Q said:

Could it be the maf sensor, cam sensors or crank sensor? 


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