n55 multiple misfires and ses

[weeeee]

This is almost a direct copy of what I have sent to BMS on the subject. I wasn't anticipating having problems from what I perceived as a simple intake swap, and will now begin tracking down the cause which may not be 100% intake related, but besides misfires the car generally does not drive as well. I know there is prior information on this issue but there didn't seem to be consistent resolution for people.

I have a 2011 135i with N55 engine, and just installed my BMS intake.

I am running a Cobb tune right now on 93 octane, no JB4 installed.

Prior to installing the intake, I never had any issues, and replaced spark plugs within the past 5k miles. Since installing the intake, two times I have driven hard now, and have gotten multiple misfires, ses light, and limp mode if I stay on the throttle.

I have seen vague references on forums to issues with the BMS intake on the N55 platform. Speculation seems to point to the volume of air being read by the MAF sensor. Some reports end with recommendations to reinstall the stock intake. Some reports end with recommendations to disconnect the MAF, but that advice seems to only apply if you are running the JB4 and with a specific map.

Anyone have recommendations for how to resolve this issue?

My process for establishing exactly what "the issue" is was going to be:

With BMS Intake Installed:
Log several gears WOT to reproduce issue
Note Codes

With Stock Intake Installed:
Log several gears WOT to try to repro without intake
If I'm able to repro with stock intake, I will start down the line of
Switching Coils From Affected Cylinders
WOT and see if the misfire follows the coil
If it misfires but doesn't seem correlated to the coil, revert to OEM spark plugs

I don't expect to be able to repro with the stock intake... So not sure what the options are to retain the BMS intake.

Is a JB4 is required to run MAFless on N55? How does stacking the JB4 and a Cobb flash tune work exactly?

[weeeee]

BMS says they haven't had any issues I mentioned in the OP with the N55 E series platform.

Here are the codes I pulled.

P2F7C
Super knocking: Injection switch-off
The diagnostic function responds to extreme
combustion knock by deactivating the injection

- If the diagnostic fault code has been logged
once, clear the ECU fault memory

- If the fault has been logged multiple times,
 check the spark plug, injector and ignition coil on
 the cylinder

P2F7A
Super-knocking, cylinder 5: Injection switch-off

P2EFE
Random/Multiple Cylinder Misfire Detected

P2F01
Cylinder 3 Misfire Detected

P2F04
Cylinder 6 Misfire Detected

P2EE0
Combustion misfiring, several cylinders: Fuel
injection deactivation

P2EEA
Combustion misfiring, cylinder 3: Fuel injection
deactivation

The fault is recognized when
the combustion stroke in a
particular cylinder is slower
than the combustion strokes
on the other cylinders.
Potential problem source(s):
- Defect in mixture formation
- Defect in ignition system
- Mechanical defect
- Defective DME

P2EF4
Combustion misfiring, cylinder 6: Fuel injection
deactivation

P2F03
Cylinder 5 Misfire Detected

P2EF1
Combustion misfiring, cylinder 5: Fuel injection
deactivation

P2EFF
Cylinder 1 Misfire Detected

P2EE4
Combustion misfiring, cylinder 1: Fuel injection
deactivation

Looking at the codes, I figured it could be related to the NGK plugs I installed a few thousand miles ago, so I went ahead and ordered and installed OEM BMW plugs. Inititally I thought the issue was gone, but a few pulls later and things got shitty again.

I will try to pull the codes again tomorrow and actually do a data log. May then go down to the 91 octane map even though I'm running 93 octane. Then switch to the stock intake.

May end up going with a pro tune but noone seems to not be offering them at the moment... maybe temporarily?

[houtan]

I would remove the intake and put the stick one back on. My car did the same thing with the BMS intake.

[weeeee]

Originally Posted by houtan

I would remove the intake and put the stick one back on. My car did the same thing with the BMS intake.

Went to stock and will do some pulls today since it's finally not raining.

[weeeee]

After reverting to stock intake: did about 6 hard pulls to redline in 2nd-4th. No misfires, knock, or hesitation.

I think this can be narrowed down to the BMS intake causing multiple misfires.

Final question: do you think this is something a pro-tuner can address, or should I return the BMS intake?

[houtan]

I will save you the trouble and tell you it made no difference unfortunately. I probably tried 5 different tunes and it made no difference.

[scythe1969]

Had the exact issue with the AFE Stage II Si Intake when I was running the stock tune. I put the stock intake back and the problem went away; I was experiencing idle surges and complete stalls at stops when the A/C was running.

Once I managed to get the Cobb setup on my car I tried the intake again. It ran well for about 6 months and then it started giving me problems again. I put the stock airbox in and the issue resolved itself.

I've looked at the intake and I have noticed that the air element is really dirty. I'm going to try cleaning it and putting it back to see if that's the current issue.

So, in my case, the Cobb Stage 1 Tune did fix the problems. but I can't help but think that the MAF can't sort out the changes of increased air flow regardless of the tune.

I'm sure that this issue is limited to only a certain number of year/series combinations as most cars can take the mod even though some can't.

I'm doing the air filter cleaning this weekend and I'll report back after a week of testing with the A/C turned on - looks like the weather in Cali is warming up...

[Rob_BMW_PNW]

No OTS map has MAF scaling for anything but a stock intake

I have a Wedge Base map on my N55, I put the BMS intake on and I got tons of corrections across all cylinders on my logs

Put the stock on back on and no corrections that are of concern

In order to truly use it, either use Jb4 or get a protune from a Cobb certified tuner (ATR Pro has Vanos and MAF scaling, but ATR does not)

[Rob_BMW_PNW]

BMS Intake log
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14

OEM Log
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14

Unsure about my throttle closure at the start but whatever. Oem shows less corrections and the corrections were at the dip and at the end when the ecu forced shifted at 7k

[scythe1969]

After a week of testing out the AFE Intake again, post cleaning, the car started with the same idle fluctuations and hesitations during acceleration. I've gone back to the stock intake system with an ITG filter - this combo works best with my Cobb, Stage 1 setup.

After looking at the notes on the Cobb tune, it does state that Stage 1 should be used with stock intake and stock filter or after market drop-in filter.

I'm thinking that I won't be able to use the AFE Intake properly until I pony up and get the custom tune done. I agree with Rob above.

[ssgm1x]

Originally Posted by Rob_BMW_PNW

BMS Intake log
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14

OEM Log
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14
http://www.datazap.me/u/robertnguyen...7-8-9-10-11-14

Unsure about my throttle closure at the start but whatever. Oem shows less corrections and the corrections were at the dip and at the end when the ecu forced shifted at 7k

I know this is an old thread but do u think maybe u had timing corrections due to the Higher IAT in the logs with BMS intake ?