N52 - Stumbling/misfires on heavier acceleration

NumericalIntegration · 12-13-2019, 09:18 PM

Like the title says, I get sporadic stumbling/misfires when at about 3/4 throttle or more. It tends to happen more at lower revs (2-3k). I can have INPA open in the passenger seat and get it to stumble/misfire but no codes show up. I recently replaced the intake VANOS solenoid and the #4 injector to fix previous codes. After I replaced these two it pulled cleanly as far as I can recall. Anyone have any suggestions or have expericed the engine stumbling but no codes being set?

The car is a manual 325i with 148k and a 3IM with the BimmerLabs 330i tune.

Saico · 12-14-2019, 05:14 AM

Usually misfires at lower revs + high load = spark problems.

juld0zer · 12-14-2019, 05:53 AM

reseat the ignition coils. Also ensure you have the correct spark plugs for your particular motor/DME.

850CSi · 12-14-2019, 06:20 PM

I'll start a thread of my own because I have a similar issue, my question to the two responders is wouldn't misfires or other coil/spark related issues throw a code?

Saico · 12-15-2019, 04:54 AM

Misfire code occurs only when misfires are permanent. DME has a misfire counter. It will not throw a code when misfire happens every now and then.

NumericalIntegration · 12-15-2019, 03:30 PM

Quote:

Originally Posted by juld0zer

reseat the ignition coils. Also ensure you have the correct spark plugs for your particular motor/DME.

Tried reseating to no avail. I have Bosch FR7NPP332 spark plugs which are correct I believe. About 15k on them.

Quote:

Originally Posted by Saico

Misfire code occurs only when misfires are permanent. DME has a misfire counter. It will not throw a code when misfire happens every now and then.

Is there a way to view a misfire counter for each cylinder through INPA or ISTA? I've tried looking but couldn't find anything.

mrnuke · 12-16-2019, 07:06 AM

Just went through this and replaced coils/plugs and all is well. BMW's enrichment is extremely good, so unless you're under high load/low RPM, they don't seem to happen consistently.

The Nightman · 12-21-2019, 11:49 PM

Quote:

Originally Posted by Saico

Misfire code occurs only when misfires are permanent. DME has a misfire counter. It will not throw a code when misfire happens every now and then.

Yup. I was experiencing intermittent misfiring and did not get any fault codes or CEL until the coil had failed completely. Replaced all of my coils after as a precaution.

gIzzE · 01-10-2020, 04:51 PM

Reset all engine adaptations in INPA.

https://www.e90post.com/forums/showthread.php?t=1684489

Silp3 · 02-11-2020, 07:38 PM

Cam position sensor. Pull out, clean off and check symptoms again.

juld0zer · 02-12-2020, 05:44 AM

Find a long hill and load it up. eg. put it into 3rd at 40km/h and floor the gas until the EML comes on. This will stress the ignition system.

Basic things first - is the oil level correct? Correct viscosity? Genuine or Mann filter? VANOS checkvalves clean?

Mojoooo0 · 02-12-2020, 10:39 PM

I had the same intermittent issue. One day i put a heavy load on the car and was able to force a CEL to register which coil # it was.

My spark plugs were replaced under 40k km ago so i knew it was coils as all of them were not new.

I went up a hill with high gear, low rpm and forced the stutter/misfires and was able to get the CEL to stay lit. I replaced the one coil with a delphi one and so far its been good for 10k km.

12-13-2019, 09:18 PM	#1
NumericalIntegration New Member 1 Rep 17 Posts Drives: 2006 325i Join Date: May 2018 Location: St. Louis, MO iTrader: (0)	N52 - Stumbling/misfires on heavier acceleration - get no codes Like the title says, I get sporadic stumbling/misfires when at about 3/4 throttle or more. It tends to happen more at lower revs (2-3k). I can have INPA open in the passenger seat and get it to stumble/misfire but no codes show up. I recently replaced the intake VANOS solenoid and the #4 injector to fix previous codes. After I replaced these two it pulled cleanly as far as I can recall. Anyone have any suggestions or have expericed the engine stumbling but no codes being set? The car is a manual 325i with 148k and a 3IM with the BimmerLabs 330i tune.
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12-14-2019, 05:14 AM	#2
Saico Private 30 Rep 85 Posts Drives: 330xi Join Date: May 2018 Location: PL iTrader: (0)	Usually misfires at lower revs + high load = spark problems.
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12-14-2019, 05:53 AM	#3
juld0zer Lieutenant Colonel 480 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	reseat the ignition coils. Also ensure you have the correct spark plugs for your particular motor/DME.
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12-14-2019, 06:20 PM	#4
850CSi 16 years and counting... 101 Rep 471 Posts Drives: '06 325i 6MT Join Date: Nov 2005 Location: Wisconsin iTrader: (2)	I'll start a thread of my own because I have a similar issue, my question to the two responders is wouldn't misfires or other coil/spark related issues throw a code? __________________ E90 325i 6MT + E61 530xiT 6AT = N52B30*2
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12-15-2019, 04:54 AM	#5
Saico Private 30 Rep 85 Posts Drives: 330xi Join Date: May 2018 Location: PL iTrader: (0)	Misfire code occurs only when misfires are permanent. DME has a misfire counter. It will not throw a code when misfire happens every now and then.
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12-16-2019, 07:06 AM	#7
mrnuke Private 21 Rep 75 Posts Drives: '11 E90 328i '09 E92 Track Car Join Date: Mar 2018 Location: Mooresville, NC iTrader: (1)	Just went through this and replaced coils/plugs and all is well. BMW's enrichment is extremely good, so unless you're under high load/low RPM, they don't seem to happen consistently.
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01-10-2020, 04:51 PM	#9
gIzzE Major General 363 Rep 5,984 Posts Drives: F11 + 911 C4 Join Date: Apr 2006 Location: Norfolk, UK. iTrader: (2)	Reset all engine adaptations in INPA. https://www.e90post.com/forums/showthread.php?t=1684489
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02-11-2020, 07:38 PM	#10
Silp3 New Member 0 Rep 27 Posts Drives: e46, FRS, Silverado, e90 Join Date: Mar 2011 Location: Boston/Fort Lauderdale iTrader: (0)	Cam position sensor. Pull out, clean off and check symptoms again.
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02-12-2020, 05:44 AM	#11
juld0zer Lieutenant Colonel 480 Rep 1,600 Posts Drives: Prev 135i 7DCT, Now 130i 6sp Join Date: Jul 2016 Location: 2153 iTrader: (0)	Find a long hill and load it up. eg. put it into 3rd at 40km/h and floor the gas until the EML comes on. This will stress the ignition system. Basic things first - is the oil level correct? Correct viscosity? Genuine or Mann filter? VANOS checkvalves clean?
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02-12-2020, 10:39 PM	#12
Mojoooo0 Registered 14 Rep 4 Posts Drives: 328xi Join Date: Apr 2018 Location: toronto iTrader: (0)	coils I had the same intermittent issue. One day i put a heavy load on the car and was able to force a CEL to register which coil # it was. My spark plugs were replaced under 40k km ago so i knew it was coils as all of them were not new. I went up a hill with high gear, low rpm and forced the stutter/misfires and was able to get the CEL to stay lit. I replaced the one coil with a delphi one and so far its been good for 10k km.
	Appreciate 0 Quote