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roller1150 roller1150 is offline
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Join Date: Nov 2021
Car: 2008 E92 335i
Default Constant #2 Misfire under WOT - replaced everything it seems... - 11-09-2021, 10:18 AM

I have a modified 335i. 6466 top mount, BMP port injection, BMP stage 3 bucket less LPFP, Eldor coils, Motiv E85 tune. Car puts down 680whp here in Denver when it works right

A cylinder #2 misfire has been haunting me for a while now under WOT after 4K in 3rd gear and beyond. I have replaced:

1. All plugs with NGK 97506 that are 2 steps colder gapped at 0.021"
2. All BMW Index 12 injectors and coded them
3. All Eldor coils
4. BMW LPFP sensor
5. BMW EKPM3 LPFP control unit and married to my VIN
6. Compression test results came in within 5% of all cylinders - thank god!

I data logged with MHD and the Fuel low pressure sensor at 4K at WOT goes from 85psi to 65 psi, then at 5K goes from 90 psi to 68psi. All signs are pointing to the LPFP going bad as what I am told e85 eats up the dual Walbro 450 pumps over time. Thoughts?

No LPFP codes have been thrown though as it is simply the #2 cylinder misfire. Is it possible it needs PR coils? Thanks guys. Any input is appreciated.

Last edited by roller1150; 11-09-2021 at 10:40 AM..
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Cannon @ BMS Cannon @ BMS is offline
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Car: Evo VIII
Default 11-09-2021, 03:41 PM

If you have any JB4 logs, please upload them.

Burger Motorsports
Home of the JB4 the worlds most popular turbocharged tuning system!

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Lofuel Lofuel is offline
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Join Date: Aug 2017
Car: 335is
Default 11-21-2021, 04:39 PM

Did you do a leak down test also? Just because the motor makes pressure don’t mean it’s holding it. Did you pull cyl 2 DI and check o-ring for blow by? Make sure car is not going open loop prior to misfire also. Fuel mode 15 you will see in MHD
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