misfire/stumble with no codes. If I were to...

borisivan · 06-05-2012, 08:50 AM

Hi,

My 2010 335xi (out of warantee) stumbles under heavy load / low RPMs. I have the BT tool and there is never a code/shadow code thrown. It tends to come and go, some days almost not reproducible, some days 5th and 6th gear will "stumble" very noticeably under heavy load.

I'm ordering new plugs and hopefully that will nail it.

The plugs are cheap, so I don't mind doing all 6. But if that doesn't nail it, and I move to suspecting a coil next, is there any recommendation besides:

* Purchase a new coil
* Swap with coil #1, drive around for a couple of days and see if the problem occurs
* If it doesn't, put the old one back, and move the new one to coil #2, etc. etc. etc.

I can do that, but I was hoping there was a better strategy. Any recommendations?

Also, when I swap the plugs, what is the recommended procedure (if any) to reset adaptations? The forum seemed to have some debate re: whether or not some people's misfires were related to swapping plugs and the engine having a hard time adjusting to the new plugs, etc. Is there anything I should do with the BT tool?

Thanks!

BMWsky · 06-05-2012, 09:20 AM

First, how is a 2010 out of warranty? Is it mileage?

Good first step is to do exactly what you're doing and changing plugs. If that doesn't do it, the problem may be harder to solve if the car isn't throwing any codes. Coils makes sense, but again, without codes you may be on a wild goose chase. Start with the plugs and see what happens.

Also, what other mods do you have?

GeorgiaTech335coupe · 06-05-2012, 09:31 AM

Have you tried forcing it to stumble/hesitate to throw a code? For instance, lug your car through 5th car and when it starts to stumble/misfire keep on the gas until you throw a limp mode and SES light. This is how I get misfire codes to pop up when I am trying to diagnose which cylinder. Not the most elegant solution, but it works.

borisivan · 06-05-2012, 09:31 AM

Hi,

yeah, miles -- commute is fairly long. ~60k right now.

No mods currently, had a JB+ w/ bypass for quite a while running ~ 75%, but starting throwing boost codes when I would get the misfire, as if the misfire scenario would allow more boost to build when the engine wasn't firing right. After removing it, no codes thrown when I get the misfire, but still get the same misfire.

Seems to only happen under strong load like 5th and 6th in low RPMS. Or at least that's the only time I really notice it. It's that brief shudder/stumble feeling. Sometimes it's just one quick hitch, sometimes it's a second or so of what feels like 7-8 small hitches/vibrations. Each 'miss' feels like I'm driving over a small crack in the road. It's not much, but you can feel it.

GeorgiaTech335coupe · 06-05-2012, 09:37 AM

Quote:

Originally Posted by borisivan

Hi,

yeah, miles -- commute is fairly long. ~60k right now.

No mods currently, had a JB+ w/ bypass for quite a while running ~ 75%, but starting throwing boost codes when I would get the misfire, as if the misfire scenario would allow more boost to build when the engine wasn't firing right. After removing it, no codes thrown when I get the misfire, but still get the same misfire.

Seems to only happen under strong load like 5th and 6th in low RPMS. Or at least that's the only time I really notice it. It's that brief shudder/stumble feeling. Sometimes it's just one quick hitch, sometimes it's a second or so of what feels like 7-8 small hitches/vibrations. Each 'miss' feels like I'm driving over a small crack in the road. It's not much, but you can feel it.

Ok. So it sounds like your misfire is still in his infancy. Don't worry tho, if left uncheck, he will grow up to be big and strong. Then it'll be easy to diagnose.

Redrkt503 · 06-05-2012, 10:48 AM

sounds exactly like when my evo had plugs that weren't gapped right... I would get on it under full boost an it would stutter and hiccup until I let off. I got new plugs gapped em right and presto! full boost and revs clean through the rpms

Slidewayz · 06-05-2012, 10:51 AM

Yeah, my car just got the 'stutters' too and not throwing any codes.

I can detect it just sitting at a standstill revving to 2k rpms. It will be running smooth, then the idle drops like it isn't getting gas, then it is fine again.

The plugs probably aren't the problem since they have about 5k miles on them.

Chipedy · 06-05-2012, 03:27 PM

I'm having the same issue. Noticeable mostly from 3rd gear and above at between 3k and 4k rmp. Spark plugs only 8k on them.

06-05-2012, 08:50 AM	#1
borisivan craptastic 18 Rep 281 Posts Drives: 2010 335xi Join Date: Jul 2007 Location: hell in a handbasket iTrader: (0)	misfire/stumble with no codes. If I were to... Hi, My 2010 335xi (out of warantee) stumbles under heavy load / low RPMs. I have the BT tool and there is never a code/shadow code thrown. It tends to come and go, some days almost not reproducible, some days 5th and 6th gear will "stumble" very noticeably under heavy load. I'm ordering new plugs and hopefully that will nail it. The plugs are cheap, so I don't mind doing all 6. But if that doesn't nail it, and I move to suspecting a coil next, is there any recommendation besides: * Purchase a new coil * Swap with coil #1, drive around for a couple of days and see if the problem occurs * If it doesn't, put the old one back, and move the new one to coil #2, etc. etc. etc. I can do that, but I was hoping there was a better strategy. Any recommendations? Also, when I swap the plugs, what is the recommended procedure (if any) to reset adaptations? The forum seemed to have some debate re: whether or not some people's misfires were related to swapping plugs and the engine having a hard time adjusting to the new plugs, etc. Is there anything I should do with the BT tool? Thanks!
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06-05-2012, 09:31 AM	#3
GeorgiaTech335coupe Lieutenant Colonel 76 Rep 1,883 Posts Drives: Black BMW 335i coupe Join Date: Mar 2007 Location: USA iTrader: (0)	Have you tried forcing it to stumble/hesitate to throw a code? For instance, lug your car through 5th car and when it starts to stumble/misfire keep on the gas until you throw a limp mode and SES light. This is how I get misfire codes to pop up when I am trying to diagnose which cylinder. Not the most elegant solution, but it works. __________________ Legal Disclaimer: Anything I or anyone else says about my vehicle on this website(e90post.com or any affiliated or nonaffiliated sites), pertaining to modifications, is only to gain acceptance from my/our peers, and does not actually represent anything actually existing on my car, and thus, cannot be held against me in any issues, i.e. warranty claims, that may arise.
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06-05-2012, 09:31 AM	#4
borisivan craptastic 18 Rep 281 Posts Drives: 2010 335xi Join Date: Jul 2007 Location: hell in a handbasket iTrader: (0)	Hi, yeah, miles -- commute is fairly long. ~60k right now. No mods currently, had a JB+ w/ bypass for quite a while running ~ 75%, but starting throwing boost codes when I would get the misfire, as if the misfire scenario would allow more boost to build when the engine wasn't firing right. After removing it, no codes thrown when I get the misfire, but still get the same misfire. Seems to only happen under strong load like 5th and 6th in low RPMS. Or at least that's the only time I really notice it. It's that brief shudder/stumble feeling. Sometimes it's just one quick hitch, sometimes it's a second or so of what feels like 7-8 small hitches/vibrations. Each 'miss' feels like I'm driving over a small crack in the road. It's not much, but you can feel it.
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06-05-2012, 10:48 AM	#6
Redrkt503 Lieutenant 31 Rep 439 Posts Drives: E92 335is Join Date: Jan 2012 Location: Ft. Lauderdale, FL iTrader: (0)	sounds exactly like when my evo had plugs that weren't gapped right... I would get on it under full boost an it would stutter and hiccup until I let off. I got new plugs gapped em right and presto! full boost and revs clean through the rpms __________________ 2011 335is "Redrkt" 6 MT DocRace 6266 Single Turbo - Fuel it stage 3 LPFP - Fuel it PI - spec stage 3+ clutch - mfactory SM flywheel - 100% E85 - VRSF 7.5" intercooler - VRSF charge pipe w/ HKS BOV - JB4 - MHD back end flash 768 whp 695 ft lbs - E85 - 32PSI
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06-05-2012, 10:51 AM	#7
Slidewayz Major 33 Rep 1,177 Posts Drives: 2007 335i Join Date: Jan 2009 Location: Oakland, CA iTrader: (5)	Yeah, my car just got the 'stutters' too and not throwing any codes. I can detect it just sitting at a standstill revving to 2k rpms. It will be running smooth, then the idle drops like it isn't getting gas, then it is fine again. The plugs probably aren't the problem since they have about 5k miles on them.
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06-05-2012, 09:20 AM	#2
BMWsky Major 24 Rep 1,244 Posts Drives: 335i Join Date: Dec 2010 Location: Webster NY iTrader: (1)	First, how is a 2010 out of warranty? Is it mileage? Good first step is to do exactly what you're doing and changing plugs. If that doesn't do it, the problem may be harder to solve if the car isn't throwing any codes. Coils makes sense, but again, without codes you may be on a wild goose chase. Start with the plugs and see what happens. Also, what other mods do you have?
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06-05-2012, 03:27 PM	#8
Chipedy Enlisted Member 0 Rep 39 Posts Drives: 2008 335xi Join Date: Apr 2012 Location: Virginia iTrader: (0)	I'm having the same issue. Noticeable mostly from 3rd gear and above at between 3k and 4k rmp. Spark plugs only 8k on them.
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