Misfire on low RPM's/cruising, fine under moderate+ load

Derek Keenan · 02-11-2021, 10:12 AM

Quote:

Originally Posted by Silent11N54

Quote:

Originally Posted by Derek Keenan

I swapped bank 1 injectors with bank 2 and coded them, first few minutes of driving it seemed fine then parked it and took it back out a few minutes later then started doing the stutter again, bank 2 was still doing the stutter and not so much bank 1, I've pretty much rulled out injectors considering it's only been bank 2, and it can't be 02s cause I've just replaced them, I also swapped bank 1 coils with bank 2 but still didn't work, I don't know what else Is left other than a walnut blast

im having a similar issue only at low rpm, stutter, hesitation. Anything past 4000rpm is smooth.

Im going to try swapping throttle body since i have a spare and inspecting the gasket there, see if it makes a difference. I have tried swapping a bunch of things with my other N54 and it still has the same stutter at low rpm. Vanos solenoids, boost solenoids, diverter valves, plugs, coils. I did feel a slight improvement when i reset the throttle adaptation for a short period of time.

Did throttle body fix the issue?

Derek Keenan · 03-15-2021, 09:00 PM

This thread is probably dead but I fixed the issue

Mason_535i · 04-03-2021, 11:18 PM

Quote:

Originally Posted by Derek Keenan

This thread is probably dead but I fixed the issue

What ended up being the solution?

Chavizard · 04-05-2021, 07:35 AM

Q

Quote:

Originally Posted by Derek Keenan

This thread is probably dead but I fixed the issue

Hi, I have the same issue. How did you solve it? Swap the msd81 or is another thing? Thanks you.

Derek Keenan · 04-11-2021, 05:58 PM

Quote:

Originally Posted by Chavizard

Q

Quote:

Originally Posted by Derek Keenan

This thread is probably dead but I fixed the issue

Hi, I have the same issue. How did you solve it? Swap the msd81 or is another thing? Thanks you.

I upgraded to msd81

Renz89 · 01-13-2022, 02:39 AM

Found this old thread, but saw all the similar problems that I have as well.

I tried the same things, changed vanos solenoids, coils, sparkplugs, index 12, vacum lines and boost solenoids. It became slightly better.
Next step was switch to MSD81, it tunred out into worse. I had the latest ZUSB7628540
Which ZUSB are you running on?

curtkare · 01-06-2023, 09:29 AM

Same issue here - When I mash throttle in high gear (below ~2000 rpm) engine suddenly gets lumpy. No codes yet on Carly scanner.

2009 335xi Coupe
N54 - no tune or mods
55k miles
6spd manual
index 12 injectors and new(ish) hi-press fuel pump
valves are a bit crusty but not due for blasting yet

Saif2018 · 01-06-2023, 01:15 PM

Quote:

Originally Posted by curtkare

Same issue here - When I mash throttle in high gear (below ~2000 rpm) engine suddenly gets lumpy. No codes yet on Carly scanner.

2009 335xi Coupe
N54 - no tune or mods
55k miles
6spd manual
index 12 injectors and new(ish) hi-press fuel pump
valves are a bit crusty but not due for blasting yet

under 2k your asking too much from the engine, the turbos are basically off boost as well and you could also potentially cause serious damage.

I would say at 2.5k if your going WOT on stock turbos.

curtkare · 01-10-2023, 01:57 PM

Thanks - definitely not my normal driving behavior, but it made me worry about impending issues. Still going to give it an STP valve bath and also check to see how the spark plugs look.

AWD Addict · 01-10-2023, 02:21 PM

Quote:

Originally Posted by Saif2018

under 2k your asking too much from the engine, the turbos are basically off boost as well and you could also potentially cause serious damage.

I would say at 2.5k if your going WOT on stock turbos.

Strongly disagree. The car should bog and certainly not boost nicely until RPMs are brought up to speed, but "lumpy" or any kind of uneven acceleration is not driver error as you intimate.

Something's wrong. The high load, low RPM WOT is likely teasing out another issue (bad injector, leak, etc)

Saif2018 · 01-11-2023, 06:27 AM

Quote:

Originally Posted by AWD Addict

Strongly disagree. The car should bog and certainly not boost nicely until RPMs are brought up to speed, but "lumpy" or any kind of uneven acceleration is not driver error as you intimate.

Something's wrong. The high load, low RPM WOT is likely teasing out another issue (bad injector, leak, etc)

My comment was in relation to going WOT at very low rpm, you should never do that, if you care about your engine that is.

I have a custom tune from JSR and he clearly in every email emphasised this.

"DO NOT DO HIGH LOAD LOW RPM PULLS ON HIGH BOOST TURBO ENGINES.. ALWAYS BE IN THE APPROPRIATE Gear"

Doing this can cause serious damage.

The owner above may well have other issues causing problems but let's not compound the situation by putting excessive strain on the engine

shpakpv · 02-28-2023, 07:03 AM

Hi there, had the same issue: misfire in random cylinder at low rpm to high. Changed coiles, spark plugs, injectors,cleaned vanos valves - didn't help. Suddenly, realized that my battery is half empty. After charging to full capacity - everything has gone! Now basically working smoothly, with normal acceleration and reaction. Still sometimes misfire at kickdown, but i don't actually use kickdown often. Probably some air leak is still there, have to check.

shpakpv · 02-28-2023, 07:51 AM

My mileage is 315000 km so, the battery was not original, 5 years old

03-15-2021, 09:00 PM	#46
Derek Keenan Private 10 Rep 91 Posts Drives: bmw 335i Join Date: Jan 2021 Location: arizona iTrader: (0)	This thread is probably dead but I fixed the issue __________________ Derek Keenan
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01-13-2022, 02:39 AM	#50
Renz89 New Member 0 Rep 5 Posts Drives: e82 135i (pre lci) 123d(lci) Join Date: Jul 2021 Location: Netherlands iTrader: (0)	Found this old thread, but saw all the similar problems that I have as well. I tried the same things, changed vanos solenoids, coils, sparkplugs, index 12, vacum lines and boost solenoids. It became slightly better. Next step was switch to MSD81, it tunred out into worse. I had the latest ZUSB7628540 Which ZUSB are you running on?
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01-06-2023, 09:29 AM	#51
curtkare Registered 0 Rep 2 Posts Drives: 2009 BMW 335xi Coupe Manual Join Date: Jan 2023 Location: Illinois iTrader: (0)	335 N54 - misifire full load low rpm Same issue here - When I mash throttle in high gear (below ~2000 rpm) engine suddenly gets lumpy. No codes yet on Carly scanner. 2009 335xi Coupe N54 - no tune or mods 55k miles 6spd manual index 12 injectors and new(ish) hi-press fuel pump valves are a bit crusty but not due for blasting yet
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01-10-2023, 01:57 PM	#53
curtkare Registered 0 Rep 2 Posts Drives: 2009 BMW 335xi Coupe Manual Join Date: Jan 2023 Location: Illinois iTrader: (0)	Thanks - definitely not my normal driving behavior, but it made me worry about impending issues. Still going to give it an STP valve bath and also check to see how the spark plugs look.
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02-28-2023, 07:03 AM	#56
shpakpv Registered 0 Rep 2 Posts Drives: Bmw e91, N46 Join Date: Feb 2023 Location: Minsk, Belarus iTrader: (0)	Almost fixed by charging battery Hi there, had the same issue: misfire in random cylinder at low rpm to high. Changed coiles, spark plugs, injectors,cleaned vanos valves - didn't help. Suddenly, realized that my battery is half empty. After charging to full capacity - everything has gone! Now basically working smoothly, with normal acceleration and reaction. Still sometimes misfire at kickdown, but i don't actually use kickdown often. Probably some air leak is still there, have to check.
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02-28-2023, 07:51 AM	#57
shpakpv Registered 0 Rep 2 Posts Drives: Bmw e91, N46 Join Date: Feb 2023 Location: Minsk, Belarus iTrader: (0)	My mileage is 315000 km so, the battery was not original, 5 years old
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