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2012 Genesis 5.0 R-Spec misfire (cylinder #2, #6) Help

Donovan_787

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Genesis Model Type
1G Genesis Sedan (2009-2014)
I have codes PO300, P0302, P0306. I was able to replace all of the spark plugs except cylinder #8. I was still getting the same codes. Initially I also had the code P0308, but somehow it went away even though I wasn’t able to get the plug out of cylinder #8 due to the high pressure fuel pump being in the way.

The car has 118,000 miles. What do you think is wrong with it? I decided to pour in Lucas injector cleaners in the gas tank and pray that it might be clogged injectors that is causing the misfiring of cylinder 2 & 6.
 

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Last edited:
Did you check the rest?

1663852926462.webp
 
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I have codes PO300, P0302, P0306. I was able to replace all of the spark plugs except cylinder #8. I was still getting the same codes. Initially I also had the code P0308, but somehow it went away even though I wasn’t able to get the plug out of cylinder #8 due to the high pressure fuel pump being in the way.

The car has 118,000 miles. What do you think is wrong with it? I decided to pour in Lucas injector cleaners in the gas tank and pray that it might be clogged injectors that is causing the misfiring of cylinder 2 & 6.
Umm...did you replace the actual ignition coil for cylinder #8?
 
Try switching the coil packs from cylinders that are not throwing any codes and see what that does. Then you might narrow down the issue to bad coil packs, or eliminate suspected bad coil packs. Make sure you note which cylinder's coil packs you are changing. And you really need to change the plug in #8 cylinder. I used a combination of 1/4 drive sockets and a universal socket. Good luck!
 
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