Missfiring and running lean need help!

MayanRosales · 12-27-2023, 08:05 PM

Currently have a 2011 e92 335i. Was running a log on MHD one day and car started to sound and feel like it was miss firing. I drove home since I wasn’t far but no codes or limp mode was activated on the dash board. Car was idling extremely bad and seemed almost as if it was taking in too much air. Also misfire does not happen until car has been drivin for a couple of minutes. Checked MHD and these were the codes it was throwing. My guess it’s eiether something to do with MAF sensor or fuel pump.

For info: car is currently FBO MHD stage2+, BMS intake

Just want some input from others who have had this issue or would know what the issue is before diving into finding the source myself. Thank you.

cmbe92guy · 12-27-2023, 08:54 PM

Blow an intercooler coupler? I’d take a look under the hood

MayanRosales · 12-28-2023, 01:26 AM

Quote:

Originally Posted by cmbe92guy

Blow an intercooler coupler? I’d take a look under the hood

I will look into it tomorrow. Thank you

gbalthrop · 12-28-2023, 12:20 PM

While you have NO specific code related to LPFP or HPFP, you have "large deviation" TOO LEAN. If you can monitor LIVE DATA of Low Pressure Sensor and Fuel Rail Sensor (High Pressure) with engine at idle, that might provide some clues.
George

MayanRosales · 12-28-2023, 06:05 PM

After some testing and logging problem seems to be solely on the airflow system. Fuel pressure was good and stayed good. I allowed the car to idle for 5-10 min and had no issues, issues started arising once I took the car for a drive. Only code that showed once old codes were cleared were 2774 (air volume too high). Could it be an issue with the MAFS or could a boost leak cause an increased intake of air?

12-27-2023, 08:05 PM	#1
MayanRosales Enlisted Member 4 Rep 34 Posts Drives: BMW 2011 e92 335I Join Date: Jan 2022 Location: Louisiana iTrader: (0) Garage List 2011 BMW 335i [0.00] 2011 bmw 335i [0.00]	Currently have a 2011 e92 335i. Was running a log on MHD one day and car started to sound and feel like it was miss firing. I drove home since I wasn’t far but no codes or limp mode was activated on the dash board. Car was idling extremely bad and seemed almost as if it was taking in too much air. Also misfire does not happen until car has been drivin for a couple of minutes. Checked MHD and these were the codes it was throwing. My guess it’s eiether something to do with MAF sensor or fuel pump. For info: car is currently FBO MHD stage2+, BMS intake Just want some input from others who have had this issue or would know what the issue is before diving into finding the source myself. Thank you. Attached Images
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12-27-2023, 08:54 PM	#2
cmbe92guy Private 101 Rep 58 Posts Drives: 2011 e92 335i xdrive Join Date: Sep 2022 Location: Cambridge iTrader: (0) Garage List 2011 e92 335i xdrive [0.00]	Blow an intercooler coupler? I’d take a look under the hood
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12-28-2023, 12:20 PM	#4
gbalthrop Brigadier General 3095 Rep 4,420 Posts Drives: 2007 328xi E91 Join Date: May 2017 Location: Fairfax Co, VA iTrader: (0)	While you have NO specific code related to LPFP or HPFP, you have "large deviation" TOO LEAN. If you can monitor LIVE DATA of Low Pressure Sensor and Fuel Rail Sensor (High Pressure) with engine at idle, that might provide some clues. George
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12-28-2023, 06:05 PM	#5
MayanRosales Enlisted Member 4 Rep 34 Posts Drives: BMW 2011 e92 335I Join Date: Jan 2022 Location: Louisiana iTrader: (0) Garage List 2011 BMW 335i [0.00] 2011 bmw 335i [0.00]	After some testing and logging problem seems to be solely on the airflow system. Fuel pressure was good and stayed good. I allowed the car to idle for 5-10 min and had no issues, issues started arising once I took the car for a drive. Only code that showed once old codes were cleared were 2774 (air volume too high). Could it be an issue with the MAFS or could a boost leak cause an increased intake of air?
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