PLEASE HELP!! n54 cylinder 5 misfire high RPM/Boost only 3,4,5,6 gear

Sep 21, 2021
22
2
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I have been chasing this problem for so long and have spent a lot of money trying to fix this problem and I am lost. I have a 2008 bmw n54 Single turbo Garrett 3884r with port injection. Car has a misfire on cylinder 5 only in high boost and High Rpms. This only happens after 2nd gear. I have swapped injectors, coilpacks, spark plugs/re gapped, checked compression, bought brand new index 12 injectors, brand new o2 sensors, got a new tuner, and it is still here. I seriously have no idea what it could be maybe a small vacuum leak of some sort? I don’t know I just want to sleep at night lol. I am sick of trying to chase it down and blowing money on it. I will post a log below with the codes I am throwing (remember this is right after I replaced injectors and o2 sensors) car also has a SMFW
82F91AF0-92CE-40BA-B430-0B8E2F7D3FC3.jpeg
Data log
 

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  • 2021-10-12 15_10_04 I8A0S v3.00 MOTIV - Jack OBrien - I8A0S E85-EBC-N20-PI-TS-VCV.mhd.csv
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N54x4

New Member
Jun 26, 2020
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Have you tried Teflon tape on the #5 injector? Seeing as you’ve tried everything else, there’s a chance the hole for the injector is ovaled out slightly, causing a misfire even with new injectors.
 
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NoGuru

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Jan 9, 2018
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Have you tried Teflon tape on the #5 injector? Seeing as you’ve tried everything else, there’s a chance the hole for the injector is ovaled out slightly, causing a misfire even with new injectors.
I was thinking the same thing while reading the post.
 
Sep 21, 2021
22
2
0
I
Have you tried Teflon tape on the #5 injector? Seeing as you’ve tried everything else, there’s a chance the hole for the injector is ovaled out slightly, causing a misfire even with new injector
Good idea, I will try that. I also am running straight wastegate which should be around 14-15 psi with the springs I have and it was making 20+ psi on gate. I am going to put in a brand new tial wastegate this weekend and see if anything changes.