E92 335xi (N55) Hesitation backfiring no codes

yayaya · 01-25-2018, 01:43 PM

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

mashimarho · 01-25-2018, 02:39 PM

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Define...... hesitating?

SnapCoupe · 01-25-2018, 03:28 PM

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Could be a fuel issue if it only happens WOT. Not getting enough fuel could cause the misfires and under WOT it causes a backfire-like racket thats quite loud. Not sure why it wouldn't throw a code though.

Does this happen on Map 0?

yayaya · 01-25-2018, 07:59 PM

Quote:

Originally Posted by mashimarho

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Define...... hesitating?

Quote:

Originally Posted by mashimarho

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Define...... hesitating?

The car stutters, I push on the accelerator and the engine cuts in and out, with loud backfires at the same time, Rpms stay constant until the stuttering stops and the engine picks up. No turbo spool during the stuttering.

yayaya · 01-25-2018, 08:01 PM

Quote:

Originally Posted by SnapCoupe

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Could be a fuel issue if it only happens WOT. Not getting enough fuel could cause the misfires and under WOT it causes a backfire-like racket thats quite loud. Not sure why it wouldn't throw a code though.

Does this happen on Map 0?

Quote:

Originally Posted by mashimarho

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Define...... hesitating?

Quote:

Originally Posted by SnapCoupe

Quote:

Originally Posted by yayaya

Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.

Could be a fuel issue if it only happens WOT. Not getting enough fuel could cause the misfires and under WOT it causes a backfire-like racket thats quite loud. Not sure why it wouldn't throw a code though.

Does this happen on Map 0?

I?ve replaced HPFP, all injectors, and plugs. I will put it on Map 0 tonight.

SnapCoupe · 01-25-2018, 08:22 PM

Quote:

Originally Posted by yayaya

I?ve replaced HPFP, all injectors, and plugs. I will put it on Map 0 tonight.

Could potentially be the LPFP. I was going to say coils, but even if you have a bad coil, it will still rev out and def throw codes.

hetzle · 01-25-2018, 08:52 PM

Quote:

Originally Posted by SnapCoupe

Could be a fuel issue if it only happens WOT. Not getting enough fuel could cause the misfires and under WOT it causes a backfire-like racket thats quite loud. Not sure why it wouldn't throw a code though.

Does this happen on Map 0?

This is what my car has been doing - I usually let off the throttle when I feel them coming on but if I continue holding the pedal down the car goes into limp mode and shuts off cylinders. Super frustrating!

Pladi · 01-26-2018, 09:25 AM

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

Toome · 01-26-2018, 12:52 PM

Quote:

Originally Posted by Pladi

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

Same thing happens to me sometimes. It just needs to be worked out in future revisions of the MHD OTS maps. For now you will get a throttle closure to save your engine under a situation where your fuel pump cannot keep up.

Here is one of my logs as an example (notice the throttle closure and hpfp not hitting its req target):
https://datazap.me/u/toome/mhd-stage...=2-17-18-22-23

yayaya · 01-26-2018, 06:55 PM

Quote:

Originally Posted by Pladi

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

Quote:

Originally Posted by Pladi

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

I have some codes:

2BEE high fuel pressure
2BF8 rail pressure sensor permanently stuck
2c01 high fuel pressure
2D15 oxygen sensor after cat
2EE2 combustion misfiring
2EE6 combustion misfiring
2EE9 combustion misfiring
2EEC combustion misfiring
2EF3 combustion misfiring
2EF6 combustion misfiring
2EFF misfire cinder 1
2F00 misfire cylinder 2
2F01 misfire cylinder 3
2F03 misfire cylinder 4
2F04 misfire cylinder 5
2F05 misfire cylinder 6

yayaya · 01-27-2018, 12:59 PM

Quote:

Originally Posted by Toome

Quote:

Originally Posted by Pladi

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

Same thing happens to me sometimes. It just needs to be worked out in future revisions of the MHD OTS maps. For now you will get a throttle closure to save your engine under a situation where your fuel pump cannot keep up.

Here is one of my logs as an example (notice the throttle closure and hpfp not hitting its req target):
https://datazap.me/u/toome/mhd-stage...=2-17-18-22-23

Quote:

Originally Posted by Toome

Quote:

Originally Posted by Pladi

Gotta love these posts. Could be this could be that. Could be 100 different things...

Get codes .. lets stop assuming

NO CEL doesnt mean no codes.. there will be shadow codes for sure..

Same thing happens to me sometimes. It just needs to be worked out in future revisions of the MHD OTS maps. For now you will get a throttle closure to save your engine under a situation where your fuel pump cannot keep up.

Here is one of my logs as an example (notice the throttle closure and hpfp not hitting its req target):
https://datazap.me/u/toome/mhd-stage...=2-17-18-22-23

Here?s my log from today Stage 0

asrautox · 01-27-2018, 01:53 PM

What fuel are you running?? Assuming your plugs and coils are healthy, there are usually two things that cause this; Throttle Closures or Fuel System limits. I've spent hours chasing these issues away from my car. For me it was fuel system limits trying to run E40. Even with solid single-gear pulls, the car would break up post shift when it went into open loop. For my car, I've got to keep loads at 190 or less and run no richer than 12.5:1 afr. If any instance occurs that doesn't meet those limits, I get misfires.

yayaya · 01-27-2018, 02:51 PM

Quote:

Originally Posted by asrautox

What fuel are you running?? Assuming your plugs and coils are healthy, there are usually two things that cause this; Throttle Closures or Fuel System limits. I've spent hours chasing these issues away from my car. For me it was fuel system limits trying to run E40. Even with solid single-gear pulls, the car would break up post shift when it went into open loop. For my car, I've got to keep loads at 190 or less and run no richer than 12.5:1 afr. If any instance occurs that doesn't meet those limits, I get misfires.

I am running pump 93.

Pladi · 01-28-2018, 03:21 PM

upload the log ill have a look dont just post a picture.. tells us nothing. post it on datazap

yayaya · 01-29-2018, 01:08 PM

Quote:

Originally Posted by Pladi

upload the log ill have a look dont just post a picture.. tells us nothing. post it on datazap

Quote:

Originally Posted by Pladi

upload the log ill have a look dont just post a picture.. tells us nothing. post it on datazap

https://datazap.me/u/chris-barta/log...og=0&data=4-14

Pladi · 01-29-2018, 02:22 PM

Quote:

Originally Posted by yayaya

https://datazap.me/u/chris-barta/log...og=0&data=4-14

Perfect.

So from that 1 log i can see that the HPFP is not holding pressure. When you opened throttle there it went up to 1800 (which should have maybe been even higher) then dips to 900 which it should not. You have issues with you HPFP. ITs weak sort of say.. Not holding pressure well.

Pladi · 01-29-2018, 02:25 PM

Quote:

Originally Posted by Pladi

Perfect.

So from that 1 log i can see that the HPFP is not holding pressure. When you opened throttle there it went up to 1800 (which should have maybe been even higher) then dips to 900 which it should not. You have issues with you HPFP. ITs weak sort of say.. Not holding pressure well.

Compare that log with this one

https://datazap.me/u/pladi/log-15153...0&data=2-16-17

Graph throttle and fuel rail pressure. See how your dips and this stays up..

Pladi · 01-29-2018, 02:30 PM

What fuel do you use i?

Pladi · 01-29-2018, 02:57 PM

Quote:

Originally Posted by Pladi

What fuel do you use i?

i just saw that sorry you said 93..

Pladi · 01-29-2018, 02:58 PM

because of your codes i would change the rail pressure sensor first.

yayaya · 01-29-2018, 06:44 PM

Quote:

Originally Posted by Pladi

because of your codes i would change the rail pressure sensor first.

Ok, I have already replaced the HPFP.

Johnny Boost · 02-05-2018, 04:22 PM

Quote:

Originally Posted by yayaya

Ok, I have already replaced the HPFP.

Were you ever able to figure out the 2bf8 code?

01-25-2018, 01:43 PM	#1
yayaya Second Lieutenant 104 Rep 263 Posts Drives: BMW 335xi E92 N55 Join Date: Dec 2016 Location: Midwest iTrader: (0)	E92 335xi (N55) Hesitation backfiring no codes Car has been hesitating and backfiring loudly under WOT but no codes. FBO MHD Stage 2.
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01-26-2018, 09:25 AM	#8
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	Gotta love these posts. Could be this could be that. Could be 100 different things... Get codes .. lets stop assuming NO CEL doesnt mean no codes.. there will be shadow codes for sure..
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01-27-2018, 01:53 PM	#12
asrautox Private First Class 19 Rep 151 Posts Drives: 2011 335xi Join Date: Jun 2011 Location: LA iTrader: (0)	What fuel are you running?? Assuming your plugs and coils are healthy, there are usually two things that cause this; Throttle Closures or Fuel System limits. I've spent hours chasing these issues away from my car. For me it was fuel system limits trying to run E40. Even with solid single-gear pulls, the car would break up post shift when it went into open loop. For my car, I've got to keep loads at 190 or less and run no richer than 12.5:1 afr. If any instance occurs that doesn't meet those limits, I get misfires. __________________ 2011 335xi M-Sport \| MHD E40 \| VSRF DP/CP \| Wagner IC \| GFB DV+ \| xHP Stage 3 \| Dinan/Koni/UUC
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01-28-2018, 03:21 PM	#14
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	upload the log ill have a look dont just post a picture.. tells us nothing. post it on datazap
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01-29-2018, 02:30 PM	#18
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	What fuel do you use i?
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01-29-2018, 02:58 PM	#20
Pladi Lieutenant Colonel 718 Rep 1,753 Posts Drives: 2011 335i xdrive Join Date: Nov 2017 Location: Waterloo, ON Canada iTrader: (0)	because of your codes i would change the rail pressure sensor first.
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